(x+10)*(2/5)=60

Solution for (x+10)*(2/5)=60 equation:

(x+10)(2/5)=60

We move all terms to the left:

(x+10)(2/5)-(60)=0

We add all the numbers together, and all the variables

(x+10)(+2/5)-60=0

We multiply parentheses ..

(+2x^2+10*2/5)-60=0

We multiply all the terms by the denominator


(+2x^2+10*2-60*5)=0

We get rid of parentheses

2x^2+10*2-60*5=0

We add all the numbers together, and all the variables

2x^2-280=0

a = 2; b = 0; c = -280;
Δ = b2-4ac
Δ = 02-4·2·(-280)
Δ = 2240
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{2240}=\sqrt{64*35}=\sqrt{64}*\sqrt{35}=8\sqrt{35}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-8\sqrt{35}}{2*2}=\frac{0-8\sqrt{35}}{4}
=-\frac{8\sqrt{35}}{4}
=-2\sqrt{35}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+8\sqrt{35}}{2*2}=\frac{0+8\sqrt{35}}{4}
=\frac{8\sqrt{35}}{4}
=2\sqrt{35}
$