Answer:
(2x - 5) • (x + 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 1 .
-30 + 1 = -29
-15 + 2 = -13
-10 + 3 = -7
-6 + 5 = -1
-5 + 6 = 1 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -5 and 6
2x2 - 5x + 6x - 15
Step-4 : Add up the first 2 terms, pulling out like factors :
x • (2x-5)
Add up the last 2 terms, pulling out common factors :
3 • (2x-5)
Step-5 : Add up the four terms of step 4 :
(x+3) • (2x-5)
Which is the desired factorization
Final result :
(2x - 5) • (x + 3)