What is the length of C D

Simonne used the following steps to simplify the given expression. 12 - 3(-2x + 4) step 1: 12 + (–3)·(–2x) + (–3)·(4) step 2: 12 + 6x + (–12) step 3: 12 + (–12) + 6x step 4: 0 + 6x step 5: 6x what property of real numbers was used to transition from step 3 to step 4? a. identity property of addition b. inverse property of addition c. associative property of addition d. commutative property of addition

Given f(x)=2x^2-8x+6 and g(x)=3x-1 find f(x) +g(x) a. 2x^2+5x+5 b.2x^2-11x+7 c. 2x^2-5x+5 d.2x^2-5x-5

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