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2\left(50-2x\right)\left(60-3x\right)-x\left(60-3x\right)=4860
Multiply both sides of the equation by 2.
\left(100-4x\right)\left(60-3x\right)-x\left(60-3x\right)=4860
Use the distributive property to multiply 2 by 50-2x.
6000-540x+12x^{2}-x\left(60-3x\right)=4860
Use the distributive property to multiply 100-4x by 60-3x and combine like terms.
6000-540x+12x^{2}-\left(60x-3x^{2}\right)=4860
Use the distributive property to multiply x by 60-3x.
6000-540x+12x^{2}-60x+3x^{2}=4860
To find the opposite of 60x-3x^{2}, find the opposite of each term.
6000-600x+12x^{2}+3x^{2}=4860
Combine -540x and -60x to get -600x.
6000-600x+15x^{2}=4860
Combine 12x^{2} and 3x^{2} to get 15x^{2}.
6000-600x+15x^{2}-4860=0
Subtract 4860 from both sides.
1140-600x+15x^{2}=0
Subtract 4860 from 6000 to get 1140.
15x^{2}-600x+1140=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(-600\right)±\sqrt{\left(-600\right)^{2}-4\times 15\times 1140}}{2\times 15}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 15 for a, -600 for b, and 1140 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-600\right)±\sqrt{360000-4\times 15\times 1140}}{2\times 15}
Square -600.
x=\frac{-\left(-600\right)±\sqrt{360000-60\times 1140}}{2\times 15}
Multiply -4 times 15.
x=\frac{-\left(-600\right)±\sqrt{360000-68400}}{2\times 15}
Multiply -60 times 1140.
x=\frac{-\left(-600\right)±\sqrt{291600}}{2\times 15}
Add 360000 to -68400.
x=\frac{-\left(-600\right)±540}{2\times 15}
Take the square root of 291600.
x=\frac{600±540}{2\times 15}
The opposite of -600 is 600.
x=\frac{600±540}{30}
Multiply 2 times 15.
x=\frac{1140}{30}
Now solve the equation x=\frac{600±540}{30} when ± is plus. Add 600 to 540.
x=38
Divide 1140 by 30.
x=\frac{60}{30}
Now solve the equation x=\frac{600±540}{30} when ± is minus. Subtract 540 from 600.
x=2
Divide 60 by 30.
x=38 x=2
The equation is now solved.
2\left(50-2x\right)\left(60-3x\right)-x\left(60-3x\right)=4860
Multiply both sides of the equation by 2.
\left(100-4x\right)\left(60-3x\right)-x\left(60-3x\right)=4860
Use the distributive property to multiply 2 by 50-2x.
6000-540x+12x^{2}-x\left(60-3x\right)=4860
Use the distributive property to multiply 100-4x by 60-3x and combine like terms.
6000-540x+12x^{2}-\left(60x-3x^{2}\right)=4860
Use the distributive property to multiply x by 60-3x.
6000-540x+12x^{2}-60x+3x^{2}=4860
To find the opposite of 60x-3x^{2}, find the opposite of each term.
6000-600x+12x^{2}+3x^{2}=4860
Combine -540x and -60x to get -600x.
6000-600x+15x^{2}=4860
Combine 12x^{2} and 3x^{2} to get 15x^{2}.
-600x+15x^{2}=4860-6000
Subtract 6000 from both sides.
-600x+15x^{2}=-1140
Subtract 6000 from 4860 to get -1140.
15x^{2}-600x=-1140
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{15x^{2}-600x}{15}=-\frac{1140}{15}
Divide both sides by 15.
x^{2}+\left(-\frac{600}{15}\right)x=-\frac{1140}{15}
Dividing by 15 undoes the multiplication by 15.
x^{2}-40x=-\frac{1140}{15}
Divide -600 by 15.
x^{2}-40x=-76
Divide -1140 by 15.
x^{2}-40x+\left(-20\right)^{2}=-76+\left(-20\right)^{2}
Divide -40, the coefficient of the x term, by 2 to get -20. Then add the square of -20 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-40x+400=-76+400
Square -20.
x^{2}-40x+400=324
Add -76 to 400.
\left(x-20\right)^{2}=324
Factor x^{2}-40x+400. 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-20\right)^{2}}=\sqrt{324}
Take the square root of both sides of the equation.
x-20=18 x-20=-18
Simplify.
x=38 x=2
Add 20 to both sides of the equation.