Can you help me simplify this?
回答 (3)
2010-03-20 12:40 pm
✔ 最佳答案
..4p^2-36----------------
5p^2+8p-21
...4(p^2-9)
=---------------
...(p+3)(5p-7)
....4(p+3)(p-3)
=-------------------- cancel out p+3
....(p+3)(5p-7)
.....4(p-3)
=------------- answer//
......5p-7
2010-03-20 1:25 pm
(4p^2 - 36)/(5p^2 + 8p - 21)
= [4(p^2 - 9)]/(5p^2 + 15p - 7p - 21)
= [4(p^2 - 3^2)]/[(5p^2 + 15p) - (7p + 21)]
= [4(p + 3)(p - 3)]/[5p(p + 3) - 7(p + 3)]
= [4(p + 3)(p - 3)]/[(p + 3)(5p - 7)]
= [4(p - 3)]/(5p - 7)
= [4(p^2 - 9)]/(5p^2 + 15p - 7p - 21)
= [4(p^2 - 3^2)]/[(5p^2 + 15p) - (7p + 21)]
= [4(p + 3)(p - 3)]/[5p(p + 3) - 7(p + 3)]
= [4(p + 3)(p - 3)]/[(p + 3)(5p - 7)]
= [4(p - 3)]/(5p - 7)
2010-03-20 12:31 pm
if you mean (4p^2-36) /( 5p^2 + 8p - 21), then factor top & bottom first.
you should get 4(p-3)(p+3) for the top and (5p-7)(p+3) for the bottom.
then cancel sets of parenthesis that are the same (top& bottom). that is the (p+3)
you'll be left with 4(p-3)/(5p-7)
you should get 4(p-3)(p+3) for the top and (5p-7)(p+3) for the bottom.
then cancel sets of parenthesis that are the same (top& bottom). that is the (p+3)
you'll be left with 4(p-3)/(5p-7)
收錄日期: 2021-05-01 13:04:06
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