0=3m^2-16m+21

Solution for 0=3m^2-16m+21 equation:

0=3m^2-16m+21

We move all terms to the left:

0-(3m^2-16m+21)=0

We add all the numbers together, and all the variables

-(3m^2-16m+21)=0

We get rid of parentheses

-3m^2+16m-21=0

a = -3; b = 16; c = -21;
Δ = b2-4ac
Δ = 162-4·(-3)·(-21)
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-2}{2*-3}=\frac{-18}{-6}
=+3
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+2}{2*-3}=\frac{-14}{-6}
=2+1/3
$