Factorize:28 – 31x – 5x2

Q36 of 137 Page 102

Factorize:
28 – 31x – 5x²

Given,

28 – 31x – 5x²

Now first find the numbers whose-

Sum = - 31 and

Product = - 5 × 28 = 140

Required numbers are 35 and 4,

So we get;

28 – 31x – 5x²

= 28 + 4x – 35x – 5x²

= 4(7 + x) – 5x(7 + x)

= (7 + x)(4 – 5x)

Factorize:

2x² – 17x – 30

Factorize:

7y² – 19y – 6

3 + 23z – 8z²

Factorize:

6x² – 5x – 6