8m^2-9=-7m

Solution for 8m^2-9=-7m equation:

8m^2-9=-7m

We move all terms to the left:

8m^2-9-(-7m)=0

We get rid of parentheses

8m^2+7m-9=0

a = 8; b = 7; c = -9;
Δ = b2-4ac
Δ = 72-4·8·(-9)
Δ = 337
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-\sqrt{337}}{2*8}=\frac{-7-\sqrt{337}}{16}
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+\sqrt{337}}{2*8}=\frac{-7+\sqrt{337}}{16}
$