Question

Giovanni justifies whether the expression -4x-8 is equivalent to -2(x+1)-2(x+3)by letting x=3 in both expressions. What is the value of each expression when x=3

3 and -20

4 and 4

-20 and -20

3 and 4

Answer 1

For this case we have the following expressions:
-4x-8
-2 (x + 1) -2 (x + 3)
Evaluating x = 3 in both expressions we have:
-4 (3) -8 = -12 - 8 = -20
-2 (x + 1) -2 (x + 3) = -2 (3 + 1) -2 (3 + 3) = -2 (4) -2 (6) = -8-12 = -20
Answer:
the value of each expression when x = 3 is:
-20 and -20