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16=\left(4m-8\right)\left(2m-6\right)
Use the distributive property to multiply 4 by m-2.
16=8m^{2}-40m+48
Use the distributive property to multiply 4m-8 by 2m-6 and combine like terms.
8m^{2}-40m+48=16
Swap sides so that all variable terms are on the left hand side.
8m^{2}-40m+48-16=0
Subtract 16 from both sides.
8m^{2}-40m+32=0
Subtract 16 from 48 to get 32.
m=\frac{-\left(-40\right)±\sqrt{\left(-40\right)^{2}-4\times 8\times 32}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, -40 for b, and 32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-\left(-40\right)±\sqrt{1600-4\times 8\times 32}}{2\times 8}
Square -40.
m=\frac{-\left(-40\right)±\sqrt{1600-32\times 32}}{2\times 8}
Multiply -4 times 8.
m=\frac{-\left(-40\right)±\sqrt{1600-1024}}{2\times 8}
Multiply -32 times 32.
m=\frac{-\left(-40\right)±\sqrt{576}}{2\times 8}
Add 1600 to -1024.
m=\frac{-\left(-40\right)±24}{2\times 8}
Take the square root of 576.
m=\frac{40±24}{2\times 8}
The opposite of -40 is 40.
m=\frac{40±24}{16}
Multiply 2 times 8.
m=\frac{64}{16}
Now solve the equation m=\frac{40±24}{16} when ± is plus. Add 40 to 24.
m=4
Divide 64 by 16.
m=\frac{16}{16}
Now solve the equation m=\frac{40±24}{16} when ± is minus. Subtract 24 from 40.
m=1
Divide 16 by 16.
m=4 m=1
The equation is now solved.
16=\left(4m-8\right)\left(2m-6\right)
Use the distributive property to multiply 4 by m-2.
16=8m^{2}-40m+48
Use the distributive property to multiply 4m-8 by 2m-6 and combine like terms.
8m^{2}-40m+48=16
Swap sides so that all variable terms are on the left hand side.
8m^{2}-40m=16-48
Subtract 48 from both sides.
8m^{2}-40m=-32
Subtract 48 from 16 to get -32.
\frac{8m^{2}-40m}{8}=-\frac{32}{8}
Divide both sides by 8.
m^{2}+\left(-\frac{40}{8}\right)m=-\frac{32}{8}
Dividing by 8 undoes the multiplication by 8.
m^{2}-5m=-\frac{32}{8}
Divide -40 by 8.
m^{2}-5m=-4
Divide -32 by 8.
m^{2}-5m+\left(-\frac{5}{2}\right)^{2}=-4+\left(-\frac{5}{2}\right)^{2}
Divide -5, the coefficient of the x term, by 2 to get -\frac{5}{2}. Then add the square of -\frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}-5m+\frac{25}{4}=-4+\frac{25}{4}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
m^{2}-5m+\frac{25}{4}=\frac{9}{4}
Add -4 to \frac{25}{4}.
\left(m-\frac{5}{2}\right)^{2}=\frac{9}{4}
Factor m^{2}-5m+\frac{25}{4}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(m-\frac{5}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
m-\frac{5}{2}=\frac{3}{2} m-\frac{5}{2}=-\frac{3}{2}
Simplify.
m=4 m=1
Add \frac{5}{2} to both sides of the equation.