solve this equation: 2d^2+9d-5=0 and check.

Question

I am having a block and I need to figure out how to solve this equation.

2d^2 +9d-5=0

Answer 1

Given trinomial 2d^2+9d-5 = 0

2d^2+10d-d-5 = 0

2d(d+5)-1(d+5) = 0

Take common out d+5 from above expression.

= (d+5)(2d-1)

d+5 = 0 and  2d-1 = 0

d+5 = 0

Subtract 5 from each side.

d = -5

and 2d-1 = 0

Add 1 to each side.

2d = 1

Divide to each side by 2.

d = 1/2

Solution d = -5 and d = 1/2.