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6 votes
6 votes
Find the missing term so that r2 + _____ + 100 forms a perfect square trinomial.

A. 10r B. 20r C. −10r D. −20r

User Scott McLeod
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1 Answer

13 votes
13 votes

Answer:

B 20r

Explanation:

r² + + 100

r² = (r ) ( ) signs are all positive. 100 = (10) (10) last number. so

(r + 10)(r + 10)

r(r+ 10) + 10(r + 10)

r² + 10r + 10r + 100

r² + 20r + 100

User Njorden
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