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m^{2}+8m-4=29
Multiply both sides of the equation by 4.
m^{2}+8m-4-29=0
Subtract 29 from both sides.
m^{2}+8m-33=0
Subtract 29 from -4 to get -33.
a+b=8 ab=-33
To solve the equation, factor m^{2}+8m-33 using formula m^{2}+\left(a+b\right)m+ab=\left(m+a\right)\left(m+b\right). To find a and b, set up a system to be solved.
-1,33 -3,11
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -33.
-1+33=32 -3+11=8
Calculate the sum for each pair.
a=-3 b=11
The solution is the pair that gives sum 8.
\left(m-3\right)\left(m+11\right)
Rewrite factored expression \left(m+a\right)\left(m+b\right) using the obtained values.
m=3 m=-11
To find equation solutions, solve m-3=0 and m+11=0.
m^{2}+8m-4=29
Multiply both sides of the equation by 4.
m^{2}+8m-4-29=0
Subtract 29 from both sides.
m^{2}+8m-33=0
Subtract 29 from -4 to get -33.
a+b=8 ab=1\left(-33\right)=-33
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as m^{2}+am+bm-33. To find a and b, set up a system to be solved.
-1,33 -3,11
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -33.
-1+33=32 -3+11=8
Calculate the sum for each pair.
a=-3 b=11
The solution is the pair that gives sum 8.
\left(m^{2}-3m\right)+\left(11m-33\right)
Rewrite m^{2}+8m-33 as \left(m^{2}-3m\right)+\left(11m-33\right).
m\left(m-3\right)+11\left(m-3\right)
Factor out m in the first and 11 in the second group.
\left(m-3\right)\left(m+11\right)
Factor out common term m-3 by using distributive property.
m=3 m=-11
To find equation solutions, solve m-3=0 and m+11=0.
\frac{1}{4}m^{2}+2m-1=\frac{29}{4}
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
\frac{1}{4}m^{2}+2m-1-\frac{29}{4}=\frac{29}{4}-\frac{29}{4}
Subtract \frac{29}{4} from both sides of the equation.
\frac{1}{4}m^{2}+2m-1-\frac{29}{4}=0
Subtracting \frac{29}{4} from itself leaves 0.
\frac{1}{4}m^{2}+2m-\frac{33}{4}=0
Subtract \frac{29}{4} from -1.
m=\frac{-2±\sqrt{2^{2}-4\times \frac{1}{4}\left(-\frac{33}{4}\right)}}{2\times \frac{1}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{4} for a, 2 for b, and -\frac{33}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-2±\sqrt{4-4\times \frac{1}{4}\left(-\frac{33}{4}\right)}}{2\times \frac{1}{4}}
Square 2.
m=\frac{-2±\sqrt{4-\left(-\frac{33}{4}\right)}}{2\times \frac{1}{4}}
Multiply -4 times \frac{1}{4}.
m=\frac{-2±\sqrt{4+\frac{33}{4}}}{2\times \frac{1}{4}}
Multiply -1 times -\frac{33}{4}.
m=\frac{-2±\sqrt{\frac{49}{4}}}{2\times \frac{1}{4}}
Add 4 to \frac{33}{4}.
m=\frac{-2±\frac{7}{2}}{2\times \frac{1}{4}}
Take the square root of \frac{49}{4}.
m=\frac{-2±\frac{7}{2}}{\frac{1}{2}}
Multiply 2 times \frac{1}{4}.
m=\frac{\frac{3}{2}}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{7}{2}}{\frac{1}{2}} when ± is plus. Add -2 to \frac{7}{2}.
m=3
Divide \frac{3}{2} by \frac{1}{2} by multiplying \frac{3}{2} by the reciprocal of \frac{1}{2}.
m=-\frac{\frac{11}{2}}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{7}{2}}{\frac{1}{2}} when ± is minus. Subtract \frac{7}{2} from -2.
m=-11
Divide -\frac{11}{2} by \frac{1}{2} by multiplying -\frac{11}{2} by the reciprocal of \frac{1}{2}.
m=3 m=-11
The equation is now solved.
\frac{1}{4}m^{2}+2m-1=\frac{29}{4}
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{1}{4}m^{2}+2m-1-\left(-1\right)=\frac{29}{4}-\left(-1\right)
Add 1 to both sides of the equation.
\frac{1}{4}m^{2}+2m=\frac{29}{4}-\left(-1\right)
Subtracting -1 from itself leaves 0.
\frac{1}{4}m^{2}+2m=\frac{33}{4}
Subtract -1 from \frac{29}{4}.
\frac{\frac{1}{4}m^{2}+2m}{\frac{1}{4}}=\frac{\frac{33}{4}}{\frac{1}{4}}
Multiply both sides by 4.
m^{2}+\frac{2}{\frac{1}{4}}m=\frac{\frac{33}{4}}{\frac{1}{4}}
Dividing by \frac{1}{4} undoes the multiplication by \frac{1}{4}.
m^{2}+8m=\frac{\frac{33}{4}}{\frac{1}{4}}
Divide 2 by \frac{1}{4} by multiplying 2 by the reciprocal of \frac{1}{4}.
m^{2}+8m=33
Divide \frac{33}{4} by \frac{1}{4} by multiplying \frac{33}{4} by the reciprocal of \frac{1}{4}.
m^{2}+8m+4^{2}=33+4^{2}
Divide 8, the coefficient of the x term, by 2 to get 4. Then add the square of 4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+8m+16=33+16
Square 4.
m^{2}+8m+16=49
Add 33 to 16.
\left(m+4\right)^{2}=49
Factor m^{2}+8m+16. 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+4\right)^{2}}=\sqrt{49}
Take the square root of both sides of the equation.
m+4=7 m+4=-7
Simplify.
m=3 m=-11
Subtract 4 from both sides of the equation.