Question

How do you factor the expression `8x^2+ 38x + 9`?

Answer 1

`8x^2+38x+9`

Find two numbers that multiply to `9*8=72` and add to `38`:
The two numbers are `2 and 36`:

`=8x^2+2x+36x+9`

`=2x(4x+1)+9(4x+1)`

`=(2x+9)(4x+1)`