Question

solve 3x 2 square -11x-20 =0

Answer 1

Answer: (x - 5) ( 3x + 4) = 0

Given :-

☯ 3x² - 11x - 20 = 0

=> 3x² - ( 15 - 4) x - 20 = 0

=> 3x² - 15x + 4x - 20 = 0

=> 3x ( x - 5 ) + 4 ( x - 5) = 0

=> ( x - 5 ) ( 3x + 4) = 0

. ° . either ,

( x - 5) = 0

x = 5

or,

( 3x + 4) = 0

3x = -4

x = -4/3

Answer 2

3x^2-11x-20

20×3=60

by splitting the middle term

3x^2-15x+4x-20

3x(x-5)+4(x-5)

3x+4=0 ( or ) x-5=0

3x = -4

x = -4/3 or x = 5