Answer:
- -5, -18
- -5x -18x
- (x -3)(6x -5)
Explanation:
a) The factors of 90 are ...
90 = (-1)(-90) = (-2)(-45) = (-3)(-30) = (-5)(-18) = (-6)(-15) = (-9)(-10)
The sums of these factors are -91, -47, -33, -23, -21, -19.
The factor pair with the sum of -23 is of interest here. Those factors are ...
-5, -18
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b) -23x = -5x -18x
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c) The rewritten expression is ...
6x^2 -5x -18x +15
(6x^2 -5x) -(18x -15) . . . . group into pairs
x(6x -5) -3(6x -5) . . . . . . .factor each pair
(x -3)(6x -5) . . . . . . . . . . factor out the common factor (6x -5)