So much you're a lifesaver : ) (question 4 has more answer if you come up with something else)

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

Which of the following are accepted without proof in a logical system? check all that apply.

What happens to the area as the sliders are adjusted? what do you think the formula for the area of a triangle is divided by 2?