IN DESCRIPTION

Question

4)  x^2 −7x−8=0

 

5)2x^2+15x=−18

Answer 1

4) x^2 −7x−8=0

or x^2 -8x +x -8 =0

or x(x-8) +1(x-8) =0

or (x+1)(x-8) =0

So, x= -1 or x =8

5) 2x^2 +15x = -18

or 2x^2 +15x +18 =0

or 2x^2 + 12x + 3x +18 =0

or 2x(x+6) + 3(x+6) =0

or (2x+3)(x+6)=0

so, x= -3/2 or x= -6