Answer:
x = 4, -4
Step-by-step explanation:
f(x)= x^2 + 7
f(x) =23
23 = x^2+7
Subtract 7 from each side
23-7 = x^2 +7-7
16 = x^2
Take the square root of each side
±sqrt(16) = sqrt(x^2)
±4 = x
A number is decreased by seven. Then, the new number is multiplied by 3 to get an answer of -9. What is the original number? ( please hurry i need to finish my assesment )
A.) - 4
B.) - 30
C.) 4
D.) 30
Answer: -4
Step-by-step explanation:reverse the steps
3(x-7)= -9
3(x-7)/3= -9/3
x-7= -3
x= -3+7
x= -4
A number is increased by 2 and then multiplied by 3. The result is 24. What is this number
Answer:
The answer is 6.
Step-by-step explanation:
To find this answer, divide 24 by 3 and you get 8. 8 minus 2 is 6.
Harry is half his brother's age. His brother is 28 years younger than their Aunt Jenny, who is five years older than Harry and his brother's dad. their dad is 31 years old. how old is Harry?
Answer:
4 years old
Step-by-step explanation:
Harry = H
Brother = B
Aunty = A
Dad = B
H = ½ B
B = A - 28
A = D + 5
D = 31
A = 31 + 5 = 36
B = 36 -28 = 8 years old
H = ½ . 8 = 4 years old
$49 per month for unlimited calling plus 5 cents for each text message. Is this proportional or non proportional?
Answer: proptional
Step-by-step explanation:
LMN is a right triangle. True or False
Answer:
False
Step-by-step explanation:
Let us check using Pythagorean Theorem
[tex]c^2 = a^2 + b^2[/tex]
Where c is the hypotenuse (14), a is the base (13) and b is the perpendicular (5)
Putting in the above formula
[tex]14^2 = 13^2 + 5^2[/tex]
196 = 169+25
196 ≠ 194
So, It is not a right angled triangle
Two numbers add to 200. The first is 20 less than the second. What are the numbers?
Answer:
Step-by-step explanation:
Let's call the first number x.
We can write an equation representing the problem using x:
x+x+20=200 (because the second number is 20 more than the first, or x)
Combine like terms: 2x+20=200
Subtract 20 from each side of the equation: 2x=180
Divide by 2: x=90
The first number is 90, the second number is 110.
Hope this helps!
Please someone help me
Answer:
y=7*3^x
Step-by-step explanation:
y=ab^x
(0,7) ⇒ 7=ab^0 ⇒ 7=a
(5, 1701) ⇒ 1701= 7b^5 ⇒ b^5=243 ⇒ b^5= 3^5 ⇒ b=3
y=7*3^x
What is the slope of the line shown?
Answer:
1/2
Step-by-step explanation:
The slope is one half, because every time x increases by 1, y increases by 1/2. You can find the slope using the rise over run strategy. You choose a point, and you also choose the point to the right of the point you first chose. You then count how many units up and to the right the right point is.
Its Up/Right.
This version of rise over run however only works when the line is going up.
A box contains 5 yellow balls, 3 blue, and 1 red ball. Two balls are drawn at random. Find the probability that the two balls are yellow
Answer:
5/18
Step-by-step explanation:
5/9 times 1/2
5/18
I may be wrong sorry
If f(x) = 3x-2 and g(x) = 2x + 1 find (f-g)(x)
Answer:
x-3
Step-by-step explanation:
f(x) = 3x-2
g(x) = 2x + 1
(f-g)(x) = 3x-2 - (2x+1)
Distribute the minus sign
=3x-2-2x-1
Combine like terms
= 3x-2x-2-1
=x-3
Can someone please help with this question.
Answer:
54cm³
Step-by-step explanation:
V=0.5*b*h
b = 3*9 = 27cm²
h=4cm
V=0.5*4*27=54cm³
A vegetable garden measures 20m x 30m. He wants to double the area by adding a strip of ground around the outside. How wide should the strip be?
Answer:
Step-by-step explanation:
part 2. Find the measure of the indicated angle to the nearest degree
Answer:
i hope this helps you
Lianne drew a sphere with a radius of 7 in. She calculated its volume and wrote it below.
Answer:
1372
Step-by-step explanation:
4x7x7x7=1372:v=4/3 pi r^3
Therefore, 1372 is the value that should be multiplied by Pi in the numerator to correctly show the volume of the sphere.
please mark me brainliest :)
Can someone help me with this question ? 10points.
What is the value of p?
Answer:
[tex]p = 43 \: \: \: degrees[/tex]
Answer A is correct
Step-by-step explanation:
[tex]90 + p = 133[/tex]
the sum of the exterior angles in a triangle is equal to the sum of opposite interior angles.
[tex]p = 133 - 90 \\ p =4 3 \: \: \: degrees[/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
What is the value of x?
20
35
60
70
HURRY PLEASE!!!!
Answer: 20
Step-by-step explanation:
Since these are vertical angles, they are equal to each other.
x+40=3x
40=2x
x=20
Find the volume of a cone. Either enter an exact answer in terms of or use 3.14 for pi and round your final answer to the nearest hundredth. The radius is 2 the height is 9
Answer:
12 units³
Step-by-step explanation:
The required formula is V = (1/3)πr²h, where r is the radius and h is the height. Here we get:
V = (1/3)π(2)²(9) = (1/3)π(9)(4) = 12 units³
Anyone mind helping out with my math?
Answer:
no
Step-by-step explanation:
all the numbers are multiples of each two.
For example,
2×2=4,
4×2=8,
8×2=16
So, the line would be linear.
// have a great day //
Hhhhhhheeeeelllllpppppppp
Answer:
tan 41 = 0.87
sin 63 = 0.89
cos 14 = 0.97
Step-by-step explanation:
No explanation since the question states to use the ALEKS calculator so you just make sure the calculator is in degrees then simply press tan 41 etc.
The cost of a service call to fix a washing machine can be expressed by the linear function Y = 45x+35, where y represents th
total cost and x represents the number of hours it takes to fix the machine. What does the y-intercept represent?
Answer: brainliesss plsss
The cost of a service call to fix a washing machine can be expressed
Step-by-step explanation:
The cost of a service call to fix a washing machine can be expressed by the linear function y=45x+35 where y represents the total cost and x represents the number of hours it takes to fix the machine.
Answer:
whats the real answer?
Step-by-step explanation:
a Fair coin is tossed 3 times. What is the probability of getting at least one heads and at least one tails?
Answer:
b. 75%
Step-by-step explanation:
Here are all the outcomes of three coin tosses:
HHH
HHT
HTH
HTT
THH
THT
TTH
TTT
There are a total of 8 possible outcomes.
1 outcome is all heads.
1 outcome is all tails.
6 outcomes have at least one heads and 1 tails
p(at least 1 heads and at least 1 tails) = 6/8 = 3/4 = 75%
Explain why a sample of 30 dentists from a large city taken to estimate the median income of all residents of that large city is not representative
Answer: Because all individuals in the sample have the same job, so the sample is biased.
Step-by-step explanation:
Ignoring the fact that 30 is a small sample for a large city, we already know that all the people in the sample has the same profession.
Now, we can expect that two dentists win have around the same income, but not all the residents in the city are dentists
A lot of them work in fast food, others may be lawyers, others may be freelancers.
We have a lot of jobs where the income does not coincide with the average income of a dentist, so with the sample of 30 dentists we are not actually representing all the other possible jobs that there are in the city.
If we want a sample that represents the income of all the residents, we should have a random sample (so the sample is not biased, like in this case).
state what additional information is required in order to know that the triangles are congruent by SSS
Answer: d) DF ≅ JH
Step-by-step explanation:
Side-Side-Side Congruency Theorem states that triangles are congruent if and only if their corresponding side lengths are congruent.
Given: EF ≅HI
Given: DE ≅IJ
Missing: DF ≅ JH
Given the function ƒ(x) = 8x^2 − 14x − 10, find ƒ(−2). A) ƒ(−2) = 50 B) ƒ(−2) = 60 C) ƒ(−2) = −6 D) ƒ(−2) = −70
Answer:
50
Step-by-step explanation:
f(x) = 8x² - 14x - 10
f(-2) = 8(-2)² - 14(-2) -10
f(-2) 8*4 + 28 - 10
f(-2) = 32 + 28 - 10 = 50
Find the angle A if angle B is 60 degrees and angle A and angle B are complementary
Answer:
30 degrees
Step-by-step explanation:
Complimentary = 90 degrees
90 - 60 = 30 degrees
HELPPPP ME PLZZZZ!!!!!!
14. Each leg is [tex]21\sqrt{2}[/tex] units long.
15 (a). The longer leg is [tex]7\sqrt{3}[/tex] units long
15 (b). The hypotenuse is [tex]14[/tex] units long
=====================================================
Explanations:
For a 45 degree right triangle, aka 45-45-90 triangle, the hypotenuse is equal to sqrt(2) times the short leg. Algebraically we can say
[tex]y = x\sqrt{2}[/tex] where x is the leg and y is the hypotenuse
Let's solve for x
[tex]y = x\sqrt{2}\\\\x\sqrt{2} = y\\\\x = \frac{y}{\sqrt{2}}\\\\x = \frac{y\sqrt{2}}{\sqrt{2}*\sqrt{2}} \ \text{rationalizing denominator}\\\\x = \frac{y\sqrt{2}}{2}\\\\[/tex]
Now plug in the given hypotenuse y = 42, this leads to,
[tex]x = \frac{y\sqrt{2}}{2}\\\\x = \frac{42\sqrt{2}}{2}\\\\x = \frac{42}{2}\sqrt{2}\\\\x = 21\sqrt{2}\\\\[/tex]
---------------------------
For a 30-60-90 triangle, the hypotenuse is double that of the short leg. So the hypotenuse is 2*7 = 14.
The longer leg is equal to sqrt(3) times the short leg. The longer leg is [tex]7\sqrt{3}[/tex]
In a group of 42 students, 9 study both Art and Biology.
10 study Biology but not Art.
7 study neither subject.
Given that a randomly selected student studies Art, what is the probability the student studies Art and Biology?
Answer:
The probability the student studies Art and Biology is 0.2143.
Step-by-step explanation:
Denote the events as follows:
A = a students studies Art
B = a students studies Biology
The information provided is:
N = 42
n (A ∩ B) = 9
n (A' ∩ B) = 10
n (A' ∩ B') = 7
Then the number of students who study Art but not Biology is:
n (A ∩ B') = N - n (A ∩ B) - n (A' ∩ B) - n (A' ∩ B')
[tex]=42-10-7-9\\\\=16[/tex]
The number of students who study Art but not Biology is 16.
Compute the probability the student studies Art and Biology as follows:
[tex]P(A\cap B)=\frac{n (A\cap B)}{N}[/tex]
[tex]=\frac{9}{42}\\\\=\frac{3}{14}\\\\=0.2143[/tex]
Thus, the probability the student studies Art and Biology is 0.2143.
Select all that apply.
Which of the following name a line in the drawings
Answer:
DB
It's the only line that is not a segment.
Step-by-step explanation:
Dos motos, A y B, toman la salida en una carrera de 90 km. La moto A realiza el recorrido con una velocidad media inferior en 20 km/h a la de la moto B, con lo que llega a la meta 3 minutos después que B. Calcula la velocidad de cada moto.
Answer:
motorcycle A: 180 km/h
motorcycle B: 200 km/h
Step-by-step explanation:
To solve this question we need to write a system of equations for A and B, using the equation:
distance = speed * time
The speed of A is 20 less than the speed of B, so:
speedA = speedB - 20
And the time A traveled is 3 minutes (0.05 hours) more than B's time, so:
timeA = timeB + 0.05
Then, using the distance equation, we have that:
distanceB = speedB * timeB
90 = speedB * timeB
distanceA = speedA * timeA
90 = (speedB - 20) * (timeB + 0.05)
90 = speedB * timeB + 0.05 * speedB - 20*timeB - 1
90 = 90 + 0.05 * speedB - 20*timeB - 1
20*timeB = 0.05 * speedB - 1
timeB = (speedB - 20)/400
using this timeB in the distance equation, we have:
90 = speedB * (speedB - 20)/400
90 * 400 = speedB^2 - 20*speedB
speedB^2 - 20*speedB - 36000 = 0
Solving this quadratic equation, we have speedB = 200 km/h
And the speedA is:
speedA = speedB - 20 = 200 - 20 = 180 km/h