Question

How to solve question 10

Answer 1

Option E
`x=x^2-10x+21`

Explanation:

we have

`x-5=√(x+4)`

we know that

For x> 5 both sides of the equation will be positive

Squared both sides

`(x-5)^2=(√(x+4))^2`

`(x-5)^2=(x+4)`

`x^2-10x+25=(x+4)`

Subtract 4 both sides

`x^2-10x+25-4=(x+4)-4`

`x^2-10x+21=x`

Rewrite

`x=x^2-10x+21`