Which of the following is a factor of x^2+x-30?
a.x+5
b.x+6
c.x+15
d.x-15
回答 (7)
✔ 最佳答案
(x + 6)(x - 5)
OPTION b.
B
The polynomial factors into (x+6)(x-5)
x^2 + x - 30
= (x + 6)(x - 5)
â´ the answer is b.
b.x+6
the factors are
(x-5) and (x+6) since by multiplying
(x-5)(x+6) = x^2 + x -30
x^2+6x-5x-30
x(x+6)-5(x+6)
(x+6)(x-5)
so, the ans is (x+6)
x^2+x-30
=> x^2 + 6x -5x -30
= x(x+6) - 5(x+6)
= (x-5)(x+6) are the factors
so the correct ans is 'b'
收錄日期: 2021-05-01 10:13:24
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