Two angles<span> are said to be supplementary when the sum of the two </span>angles<span> is </span>180<span>°. ... All </span>angles<span> that are either exterior </span>angles<span>, </span>interior angles<span>, </span>alternate angles<span> or corresponding </span>angles<span> are all congruent.</span>
Subtract 2b by both sides which gets -b+4=-5 then subtract 4 by both sides so you get -b=-9 and divide -1 by both sides so that b=9

Step-by-step explanation:
Given polynomials are:

Both polynomials have to be multiplied. We will use distributive property for the said purpose
So,

Combining alike terms

Hence,

Keywords: Polynomials, Multiplication
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The first time is 4 over 5 and the second time is 1 over 5