a) 3xy-7yz+5xz-xy-yz-+7xz
b) ⁴5x₂+x⁴ -7x³-x⁴-x³-x²+x⁴-2x₂
c) (4x-3xy+-5+y)
d)(25x²-10yx+8x²+12xy-9y²-x²y²

answer: (c) m∠qpo + (2x + 16)° = 180°

step-by-step explanation:

the opposite angles of a quadrilateral are supplementary.

so, ∠o + ∠q = 180°   and   ∠p + ∠r = 180°

since ∠r = 2x + 16°, we can use substitution as follows:

∠p + ∠r = 180°

∠p + (2x + 16)° = 180°

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8