Answer:
4 • (x - 5) • (2x + 3)
Explanation:
Step-1 : Multiply the coefficient of the first term by the constant 2 • -15 = -30
Step-2 : Find two factors of -30 whose sum equals the coefficient of the middle term, which is -7 .
-30 + 1 = -29
-15 + 2 = -13
-10 + 3 = -7 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -10 and 3
2x2 - 10x + 3x - 15
Step-4 : Add up the first 2 terms, pulling out like factors :
2x • (x-5)
Add up the last 2 terms, pulling out common factors :
3 • (x-5)
Step-5 : Add up the four terms of step 4 :
(2x+3) • (x-5)
Which is the desired factorization