Question

Can someone please help me on 7

Answer 1

Answer:

B

Step-by-step explanation:

plug in 5

5^2-5(4)+7=12

Answer 2

Answer: B.  f(x) = x^2-4x+7

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Work Shown:

A.

f(x) = 3x-8

f(5) = 3*5-8 ... replace every x with 5; simplify with PEMDAS

f(5) = 15-8

f(5) = 7

We can cross choice A off the list since we got 7 as an output, instead of 12.

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B.

f(x) = x^2-4x+7

f(5) = (5)^2-4(5)+7

f(5) = 25-4(5)+7

f(5) = 25-20+7

f(5) = 5+7

f(5) = 12

We got the output we wanted. So we can stop here.

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If you're curious about the others, then,

C.

f(x) = -x+14

f(5) = -5+14

f(5) = 9

That doesn't work, so we cross choice C off the list.

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D.

f(x) = |x-7|

f(5) = |5-7|

f(5) = |-2|

f(5) = 2

Choice D is crossed out as well.

So only choice B works.