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x^{2}-16x=-48
Swap sides so that all variable terms are on the left hand side.
x^{2}-16x+48=0
Add 48 to both sides.
a+b=-16 ab=48
To solve the equation, factor x^{2}-16x+48 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,-48 -2,-24 -3,-16 -4,-12 -6,-8
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 48.
-1-48=-49 -2-24=-26 -3-16=-19 -4-12=-16 -6-8=-14
Calculate the sum for each pair.
a=-12 b=-4
The solution is the pair that gives sum -16.
\left(x-12\right)\left(x-4\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=12 x=4
To find equation solutions, solve x-12=0 and x-4=0.
x^{2}-16x=-48
Swap sides so that all variable terms are on the left hand side.
x^{2}-16x+48=0
Add 48 to both sides.
a+b=-16 ab=1\times 48=48
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+48. To find a and b, set up a system to be solved.
-1,-48 -2,-24 -3,-16 -4,-12 -6,-8
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 48.
-1-48=-49 -2-24=-26 -3-16=-19 -4-12=-16 -6-8=-14
Calculate the sum for each pair.
a=-12 b=-4
The solution is the pair that gives sum -16.
\left(x^{2}-12x\right)+\left(-4x+48\right)
Rewrite x^{2}-16x+48 as \left(x^{2}-12x\right)+\left(-4x+48\right).
x\left(x-12\right)-4\left(x-12\right)
Factor out x in the first and -4 in the second group.
\left(x-12\right)\left(x-4\right)
Factor out common term x-12 by using distributive property.
x=12 x=4
To find equation solutions, solve x-12=0 and x-4=0.
x^{2}-16x=-48
Swap sides so that all variable terms are on the left hand side.
x^{2}-16x+48=0
Add 48 to both sides.
x=\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\times 48}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -16 for b, and 48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±\sqrt{256-4\times 48}}{2}
Square -16.
x=\frac{-\left(-16\right)±\sqrt{256-192}}{2}
Multiply -4 times 48.
x=\frac{-\left(-16\right)±\sqrt{64}}{2}
Add 256 to -192.
x=\frac{-\left(-16\right)±8}{2}
Take the square root of 64.
x=\frac{16±8}{2}
The opposite of -16 is 16.
x=\frac{24}{2}
Now solve the equation x=\frac{16±8}{2} when ± is plus. Add 16 to 8.
x=12
Divide 24 by 2.
x=\frac{8}{2}
Now solve the equation x=\frac{16±8}{2} when ± is minus. Subtract 8 from 16.
x=4
Divide 8 by 2.
x=12 x=4
The equation is now solved.
x^{2}-16x=-48
Swap sides so that all variable terms are on the left hand side.
x^{2}-16x+\left(-8\right)^{2}=-48+\left(-8\right)^{2}
Divide -16, the coefficient of the x term, by 2 to get -8. Then add the square of -8 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-16x+64=-48+64
Square -8.
x^{2}-16x+64=16
Add -48 to 64.
\left(x-8\right)^{2}=16
Factor x^{2}-16x+64. 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(x-8\right)^{2}}=\sqrt{16}
Take the square root of both sides of the equation.
x-8=4 x-8=-4
Simplify.
x=12 x=4
Add 8 to both sides of the equation.