How do you factor 90a2b2+45ab+10?
1 Answer
Jan 27, 2017
Complete the square to find:
90a2b2+45ab+10=58(12ab+3−√7i)(12ab+3+√7i)
Explanation:
85(90a2b2+45ab+10)=144a2b2+72ab+16
85(90a2b2+45ab+10)=(12ab)2+2(12ab)(3)+32+7
85(90a2b2+45ab+10)=(12ab+3)2−(√7i)2
85(90a2b2+45ab+10)=(12ab+3−√7i)(12ab+3+√7i)
So:
90a2b2+45ab+10=58(12ab+3−√7i)(12ab+3+√7i)