giovanni justifies what is expression -4x - 8 is equivalent to -2( x + 1) - 2 ( x + 3 ) by letting x equal 3 in both expressions what is the value of each expression when x equals 3

Hello!

You put 3 in for x in both equations

Equation 1
-4(3) - 8 = 

Multiply

-12 - 8 = -20

The answer is one of the ones with -20
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Equation 2
-2(3 + 1) - 2(3 + 3)

Do what is in paraenthesis

-2(4) - 2(6)

Multiply

-8 - 12 = -20
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The answer is C) -20 and -20

Hope this helps!