7x2+9x=10

Solution for 7x2+9x=10 equation:

7x^2+9x=10

We move all terms to the left:

7x^2+9x-(10)=0

a = 7; b = 9; c = -10;
Δ = b2-4ac
Δ = 92-4·7·(-10)
Δ = 361
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{361}=19$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(9)-19}{2*7}=\frac{-28}{14}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+19}{2*7}=\frac{10}{14}
=5/7
$