Question 209413
x^2 +16x +64
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Sign  of  last  term  is  (+),  therefore  factors  are  the  same,  and  add  (to 16)
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Sign  of  second  term  is  (+), therefore factors  are  (+)
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factors  of  1st  term  are  just  1*1
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factors  of  last  term  can be; 1*64,2*32,4*16,8*8
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Since  they  must  add  to  16,  lets  try  8*8,,,(8+8=16)
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(x+8)(x+8)
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check  by  FOIL,,x^2 +8x+8x+64= x^2 +16x +64,,,,,ok
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