45x^2+56x=-16

Solution for 45x^2+56x=-16 equation:

45x^2+56x=-16

We move all terms to the left:

45x^2+56x-(-16)=0

We add all the numbers together, and all the variables

45x^2+56x+16=0

a = 45; b = 56; c = +16;
Δ = b2-4ac
Δ = 562-4·45·16
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(56)-16}{2*45}=\frac{-72}{90}
=-4/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(56)+16}{2*45}=\frac{-40}{90}
=-4/9
$