Use mental math to approximate what a 15% tip would be for a bill of $31.99.

For the given quadratic equation convert into vertex form, find the vertex and find the value for x=6 y=-2x^2+2x+2

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

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.