Question

If f(x) = 5x + 40, what is f\x) when x = -5?
-9
-8
7
15

Answer 1

15

Explanation:

f(x)=5x+40

f(x)=5(-5)+40

f(x)=-25+40

f(x)=15

Answer 2

You must replace x with -5 and solve using the rules of PEMDAS (Parentheses, Exponent, Multiplication, Division, Addition, Subtraction) REMEMBER: IF NOT APPLICABLE TO THE EQUATION YOU MAY SKIP THAT STEP IN PEMDAS .

5(-5) + 40

Multiplication...

5 * -5 = -25

-25 + 40

Addition...

When adding a positive number with a negative number you will act as if you are subtracting the two numbers, then take the sign of the largest number. In this case the largest number is 40 and its sign is positive. Your answer will have a posititve sign.

-25 + 40 ----> 40 - 25 = 15

-25 + 40 = 15

15

Hope this helped!

~Just a girl in love with Shawn Mendes