Question

Let f(x)= 2x2−3x+8 What is the value of f(-4)?

Answer 1

Answer:

52

Step-by-step explanation:

So we have the function:

$f(x)=2x^2-3x+8$

And we want to find f(-4).

To find f(-4), substitute -4 for x. Thus:

$f(-4)=2(-4)^2-3(-4)+8$

Square:

$f(-4)=2(16)-3(-4)+8$

Multiply:

$f(-4)=32+12+8$

Add:

$f(-4)=44+8$

Add:

$f(-4)=52$

And we're done!

Our answer is 52.

Answer 2

Answer:

f(-4)=52

Step-by-step explanation:

We are given the function:

$f(x)=2x^2-3x+8$

We want to find f(-4), so we must substitute -4 in for x.

$f(-4)=2(-4)^2-3(-4)+8$

Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition and Subtraction.

Evaluate the exponent first.

⇒ (-4)²= -4*-4 = 16

$f(-4)=2(16)-3(-4)+8$

Multiply 2 and 16.

⇒ 2*16=32

$f(-4)=32-3(-4)+8$

Multiply -3 and -4.

⇒-3*-4=12

$f(-4)=32+12+8$

Add the three numbers together.

$f(-4)=44+8\\\\f(-4)=52$

f(-4) for the function f(x)=2x²-3x+8 is equal to 52