SOLUTION: Please help me solve this equation: {{{ 25+9r^4+r^8}}} this is factor completely

Algebra ->  Test -> SOLUTION: Please help me solve this equation: {{{ 25+9r^4+r^8}}} this is factor completely      Log On


   

Question 639019: Please help me solve this equation: +25%2B9r%5E4%2Br%5E8 this is factor completely
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Factor:
+25%2B9r%5E4%2Br%5E8
take sum of sqrt of end terms and expand by squaring
%285%2Br%5E4%29%5E2=%2825%2B10r%5E4%2Br%5E8%29+-r%5E4
%285%2Br%5E4%29%5E2-r%5E4
difference of 2 squares
%285%2Br%5E4%2Br%5E2%29%285%2Br%5E4-r%5E2%29