solve and check : 2x^2-18x+28 please

Question

i need the steps on how to factor this polynomial by grouping please.

Answer 1

Given polynomial 2x^2-18x+28

= 2x^2-14x-4x+28

= 2x(x-7)-4(x-7)

Take common out (x-7) from above polunomial.

= (x-7)(2x-4)

To solve x-7 = 0 and 2x-4 = 0

x-7 = 0

Add 7 to each side.

x = 7

And 2x-4 = 0

Add 4 to each side.

2x = 4

Divide to each side by 2.

x = 2

Solution x = 2 and 7.

Check :

2x^2-18x+28

For x = 2

= 2(4)-18(2)+28

= 8-36+28

= 0

For x = 7

= 2(49)-18(7)+28

= 98-126+28

= 0