Question

How do you solve `2x^2 + 9x = 8`?

Answer 1

Re-write the n equation in standard form then apply the quadratic formula

Explanation:

General standard form for a quadratic:
`color(white)("XXX")color(red)(a)x^2+color(blue)(b)x+color(green)(c)=0`
Quadratic formula for roots:
`color(white)("XXX")x=(-color(blue)(b)+-sqrt(color(blue)(b)^2-4color(red)(a)color(green)(c)))/(2color(red)(a))`

`2x^2+9x=8`
expressed in standard form:
`color(white)("XXX")color(red)(2)x^2+color(blue)(9)+color(green)((-8))=0`

Solutions:
`color(white)("XXX")x=(-color(blue)(9)+-sqrt(color(blue)(9)^2-4(color(red)(2))(color(green)(-8))))/(2(color(red)(2)))`

`color(white)("XXXx")=(-9+-sqrt(145))/4`