Question

Helppppp !!!

What are the solutions to 2x2 + 7x = 4? Select all that apply.
1/2
4
-1/2
-4
7
-7

Answer 1

x=-4 and x=1/2

Explanation:

The formula to solve a quadratic equation of the form

`ax^(2) +bx+c=0`

is equal to

`x=\frac{-b(+/-)\sqrt{b^(2)-4ac}} {2a}`

in this problem we have

`2x^(2) +7x=4`

equate to zero

`2x^(2) +7x-4=0`

so

`a=2\\b=7\\c=-4`

substitute in the formula

`x=\frac{-7(+/-)\sqrt{7^(2)-4(2)(-4)}} {2(2)}`

`x=\frac{-7(+/-)√(81)} {4}`

`x=\frac{-7(+/-)9} {4}`

`x=\frac{-7(+)9} {4}=(1)/(2)`

`x=\frac{-7(-)9} {4}=-4`

therefore

The solutions are

x=-4 and x=1/2