Question

Factorise 2x^2+11x-21

Answer 1

2x2-14x+3x-21
2x(x-7)+3(x-7)
(x-7)(2x+3)

Answer 2

hi mate,

solution:

Factoring 2x²+11x-21

2x² - 3x + 14x - 21

Step-1 : Add up the first 2 terms, pulling out like factors :

x • (2x-3)

Add up the last 2 terms, pulling out common factors :

7 • (2x-3)

Step-2 : Add up the four terms of step 2 :

(x+7) • (2x-3)

Which is the desired factorization

Final result :

(2x - 3) • (x + 7)

2x- 3 = 0 and x+7 = 0

x = 3/2 and x = - 7

i hope it helps you..