Explain solving systems of equations using substition?

when solving a system of equations the difference between that and elimination is the when you're using the Elimination u have to first multiply the numbers but when substituting it's different unlike the Elimination this is all ik and can u mark me brainliest?

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°

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