Question

2n2 + 7 = -4n + 5help pls ?

Answer 1

Given:

`2n^2+7=-4n+5`

Required:

We need to find the value of n.

Step-by-step explanation:

Subtract 5 from both sides of the equation.

`2n^2+7-5=-4n+5-5`

`2n^2+2=-4n`

Add 4n to both sides of the equation.

`2n^2+2+4n=-4n+4n`

`2n^2+2+4n=0`
`2n^2+4n+2=0`

DIvide both sides of the equation by 2.

`(2n^2)/(2)+(4n)/(2)+(2)/(2)=0`

`n^2+2n+1=0`
`Use\text{ 2n=n+n.}`

`n^2+n+n+1=0`

Take out the common multiple.

`n(n+1)+1(n+1)=0`

`(n+1)(n+1)=0`

`(n+1)^2=0`

`n+1=0`

Subtract 1 from both sides.

`n+1-1=0-1`
`n=-1`

Final answer:

`n=-1`