((x2-9))/(10)=4

Solution for ((x2-9))/(10)=4 equation:

((x2-9))/(10)=4

We move all terms to the left:

((x2-9))/(10)-(4)=0

We add all the numbers together, and all the variables

((+x^2-9))/10-4=0

We multiply all the terms by the denominator


((+x^2-9))-4*10=0


We calculate terms in parentheses: +((+x^2-9)), so:

(+x^2-9)

We get rid of parentheses

x^2-9

Back to the equation:

+(x^2-9)


We add all the numbers together, and all the variables

(x^2-9)-40=0

We get rid of parentheses

x^2-9-40=0

We add all the numbers together, and all the variables

x^2-49=0

a = 1; b = 0; c = -49;
Δ = b2-4ac
Δ = 02-4·1·(-49)
Δ = 196
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{196}=14$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-14}{2*1}=\frac{-14}{2}
=-7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+14}{2*1}=\frac{14}{2}
=7
$