Solve for x
x=15
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29\left(9-6x+5x^{2}\right)=36-144x+144x^{2}
Multiply 1 and 29 to get 29.
261-174x+145x^{2}=36-144x+144x^{2}
Use the distributive property to multiply 29 by 9-6x+5x^{2}.
261-174x+145x^{2}-36=-144x+144x^{2}
Subtract 36 from both sides.
225-174x+145x^{2}=-144x+144x^{2}
Subtract 36 from 261 to get 225.
225-174x+145x^{2}+144x=144x^{2}
Add 144x to both sides.
225-30x+145x^{2}=144x^{2}
Combine -174x and 144x to get -30x.
225-30x+145x^{2}-144x^{2}=0
Subtract 144x^{2} from both sides.
225-30x+x^{2}=0
Combine 145x^{2} and -144x^{2} to get x^{2}.
x^{2}-30x+225=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-30 ab=225
To solve the equation, factor x^{2}-30x+225 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,-225 -3,-75 -5,-45 -9,-25 -15,-15
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 225.
-1-225=-226 -3-75=-78 -5-45=-50 -9-25=-34 -15-15=-30
Calculate the sum for each pair.
a=-15 b=-15
The solution is the pair that gives sum -30.
\left(x-15\right)\left(x-15\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
\left(x-15\right)^{2}
Rewrite as a binomial square.
x=15
To find equation solution, solve x-15=0.
29\left(9-6x+5x^{2}\right)=36-144x+144x^{2}
Multiply 1 and 29 to get 29.
261-174x+145x^{2}=36-144x+144x^{2}
Use the distributive property to multiply 29 by 9-6x+5x^{2}.
261-174x+145x^{2}-36=-144x+144x^{2}
Subtract 36 from both sides.
225-174x+145x^{2}=-144x+144x^{2}
Subtract 36 from 261 to get 225.
225-174x+145x^{2}+144x=144x^{2}
Add 144x to both sides.
225-30x+145x^{2}=144x^{2}
Combine -174x and 144x to get -30x.
225-30x+145x^{2}-144x^{2}=0
Subtract 144x^{2} from both sides.
225-30x+x^{2}=0
Combine 145x^{2} and -144x^{2} to get x^{2}.
x^{2}-30x+225=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-30 ab=1\times 225=225
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+225. To find a and b, set up a system to be solved.
-1,-225 -3,-75 -5,-45 -9,-25 -15,-15
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 225.
-1-225=-226 -3-75=-78 -5-45=-50 -9-25=-34 -15-15=-30
Calculate the sum for each pair.
a=-15 b=-15
The solution is the pair that gives sum -30.
\left(x^{2}-15x\right)+\left(-15x+225\right)
Rewrite x^{2}-30x+225 as \left(x^{2}-15x\right)+\left(-15x+225\right).
x\left(x-15\right)-15\left(x-15\right)
Factor out x in the first and -15 in the second group.
\left(x-15\right)\left(x-15\right)
Factor out common term x-15 by using distributive property.
\left(x-15\right)^{2}
Rewrite as a binomial square.
x=15
To find equation solution, solve x-15=0.
29\left(9-6x+5x^{2}\right)=36-144x+144x^{2}
Multiply 1 and 29 to get 29.
261-174x+145x^{2}=36-144x+144x^{2}
Use the distributive property to multiply 29 by 9-6x+5x^{2}.
261-174x+145x^{2}-36=-144x+144x^{2}
Subtract 36 from both sides.
225-174x+145x^{2}=-144x+144x^{2}
Subtract 36 from 261 to get 225.
225-174x+145x^{2}+144x=144x^{2}
Add 144x to both sides.
225-30x+145x^{2}=144x^{2}
Combine -174x and 144x to get -30x.
225-30x+145x^{2}-144x^{2}=0
Subtract 144x^{2} from both sides.
225-30x+x^{2}=0
Combine 145x^{2} and -144x^{2} to get x^{2}.
x^{2}-30x+225=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(-30\right)±\sqrt{\left(-30\right)^{2}-4\times 225}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -30 for b, and 225 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-30\right)±\sqrt{900-4\times 225}}{2}
Square -30.
x=\frac{-\left(-30\right)±\sqrt{900-900}}{2}
Multiply -4 times 225.
x=\frac{-\left(-30\right)±\sqrt{0}}{2}
Add 900 to -900.
x=-\frac{-30}{2}
Take the square root of 0.
x=\frac{30}{2}
The opposite of -30 is 30.
x=15
Divide 30 by 2.
29\left(9-6x+5x^{2}\right)=36-144x+144x^{2}
Multiply 1 and 29 to get 29.
261-174x+145x^{2}=36-144x+144x^{2}
Use the distributive property to multiply 29 by 9-6x+5x^{2}.
261-174x+145x^{2}+144x=36+144x^{2}
Add 144x to both sides.
261-30x+145x^{2}=36+144x^{2}
Combine -174x and 144x to get -30x.
261-30x+145x^{2}-144x^{2}=36
Subtract 144x^{2} from both sides.
261-30x+x^{2}=36
Combine 145x^{2} and -144x^{2} to get x^{2}.
-30x+x^{2}=36-261
Subtract 261 from both sides.
-30x+x^{2}=-225
Subtract 261 from 36 to get -225.
x^{2}-30x=-225
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.
x^{2}-30x+\left(-15\right)^{2}=-225+\left(-15\right)^{2}
Divide -30, the coefficient of the x term, by 2 to get -15. Then add the square of -15 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-30x+225=-225+225
Square -15.
x^{2}-30x+225=0
Add -225 to 225.
\left(x-15\right)^{2}=0
Factor x^{2}-30x+225. 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-15\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-15=0 x-15=0
Simplify.
x=15 x=15
Add 15 to both sides of the equation.
x=15
The equation is now solved. Solutions are the same.
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