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x^{2}+3-2\left(x+4\right)=30
Multiply both sides of the equation by 6, the least common multiple of 6,3.
x^{2}+3-2x-8=30
Use the distributive property to multiply -2 by x+4.
x^{2}-5-2x=30
Subtract 8 from 3 to get -5.
x^{2}-5-2x-30=0
Subtract 30 from both sides.
x^{2}-35-2x=0
Subtract 30 from -5 to get -35.
x^{2}-2x-35=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=-35
To solve the equation, factor x^{2}-2x-35 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,-35 5,-7
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -35.
1-35=-34 5-7=-2
Calculate the sum for each pair.
a=-7 b=5
The solution is the pair that gives sum -2.
\left(x-7\right)\left(x+5\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=7 x=-5
To find equation solutions, solve x-7=0 and x+5=0.
x^{2}+3-2\left(x+4\right)=30
Multiply both sides of the equation by 6, the least common multiple of 6,3.
x^{2}+3-2x-8=30
Use the distributive property to multiply -2 by x+4.
x^{2}-5-2x=30
Subtract 8 from 3 to get -5.
x^{2}-5-2x-30=0
Subtract 30 from both sides.
x^{2}-35-2x=0
Subtract 30 from -5 to get -35.
x^{2}-2x-35=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=1\left(-35\right)=-35
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-35. To find a and b, set up a system to be solved.
1,-35 5,-7
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -35.
1-35=-34 5-7=-2
Calculate the sum for each pair.
a=-7 b=5
The solution is the pair that gives sum -2.
\left(x^{2}-7x\right)+\left(5x-35\right)
Rewrite x^{2}-2x-35 as \left(x^{2}-7x\right)+\left(5x-35\right).
x\left(x-7\right)+5\left(x-7\right)
Factor out x in the first and 5 in the second group.
\left(x-7\right)\left(x+5\right)
Factor out common term x-7 by using distributive property.
x=7 x=-5
To find equation solutions, solve x-7=0 and x+5=0.
x^{2}+3-2\left(x+4\right)=30
Multiply both sides of the equation by 6, the least common multiple of 6,3.
x^{2}+3-2x-8=30
Use the distributive property to multiply -2 by x+4.
x^{2}-5-2x=30
Subtract 8 from 3 to get -5.
x^{2}-5-2x-30=0
Subtract 30 from both sides.
x^{2}-35-2x=0
Subtract 30 from -5 to get -35.
x^{2}-2x-35=0
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.
x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-35\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and -35 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\left(-35\right)}}{2}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4+140}}{2}
Multiply -4 times -35.
x=\frac{-\left(-2\right)±\sqrt{144}}{2}
Add 4 to 140.
x=\frac{-\left(-2\right)±12}{2}
Take the square root of 144.
x=\frac{2±12}{2}
The opposite of -2 is 2.
x=\frac{14}{2}
Now solve the equation x=\frac{2±12}{2} when ± is plus. Add 2 to 12.
x=7
Divide 14 by 2.
x=-\frac{10}{2}
Now solve the equation x=\frac{2±12}{2} when ± is minus. Subtract 12 from 2.
x=-5
Divide -10 by 2.
x=7 x=-5
The equation is now solved.
x^{2}+3-2\left(x+4\right)=30
Multiply both sides of the equation by 6, the least common multiple of 6,3.
x^{2}+3-2x-8=30
Use the distributive property to multiply -2 by x+4.
x^{2}-5-2x=30
Subtract 8 from 3 to get -5.
x^{2}-2x=30+5
Add 5 to both sides.
x^{2}-2x=35
Add 30 and 5 to get 35.
x^{2}-2x+1=35+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=36
Add 35 to 1.
\left(x-1\right)^{2}=36
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{36}
Take the square root of both sides of the equation.
x-1=6 x-1=-6
Simplify.
x=7 x=-5
Add 1 to both sides of the equation.