1/5s-11/7s=7/15

Solution for 1/5s-11/7s=7/15 equation:

1/5s-11/7s=7/15

We move all terms to the left:

1/5s-11/7s-(7/15)=0


Domain of the equation: 5s!=0

s!=0/5

s!=0

s∈R



Domain of the equation: 7s!=0

s!=0/7

s!=0

s∈R


We add all the numbers together, and all the variables

1/5s-11/7s-(+7/15)=0

We get rid of parentheses

1/5s-11/7s-7/15=0

We calculate fractions


(-1715s^2)/525s^2+105s/525s^2+(-825s)/525s^2=0

We multiply all the terms by the denominator


(-1715s^2)+105s+(-825s)=0

We get rid of parentheses

-1715s^2+105s-825s=0

We add all the numbers together, and all the variables

-1715s^2-720s=0

a = -1715; b = -720; c = 0;
Δ = b2-4ac
Δ = -7202-4·(-1715)·0
Δ = 518400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{518400}=720$
$s_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-720)-720}{2*-1715}=\frac{0}{-3430}
=0
$
$s_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-720)+720}{2*-1715}=\frac{1440}{-3430}
=-144/343
$