10x2+7x+9=8

Solution for 10x2+7x+9=8 equation:

10x^2+7x+9=8

We move all terms to the left:

10x^2+7x+9-(8)=0

We add all the numbers together, and all the variables

10x^2+7x+1=0

a = 10; b = 7; c = +1;
Δ = b2-4ac
Δ = 72-4·10·1
Δ = 9
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9}=3$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-3}{2*10}=\frac{-10}{20}
=-1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+3}{2*10}=\frac{-4}{20}
=-1/5
$