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x\left(5x-7\right)=\left(x-3\right)\left(4x-3\right)
Variable x cannot be equal to any of the values 0,3 since division by zero is not defined. Multiply both sides of the equation by x\left(x-3\right), the least common multiple of x-3,x.
5x^{2}-7x=\left(x-3\right)\left(4x-3\right)
Use the distributive property to multiply x by 5x-7.
5x^{2}-7x=4x^{2}-15x+9
Use the distributive property to multiply x-3 by 4x-3 and combine like terms.
5x^{2}-7x-4x^{2}=-15x+9
Subtract 4x^{2} from both sides.
x^{2}-7x=-15x+9
Combine 5x^{2} and -4x^{2} to get x^{2}.
x^{2}-7x+15x=9
Add 15x to both sides.
x^{2}+8x=9
Combine -7x and 15x to get 8x.
x^{2}+8x-9=0
Subtract 9 from both sides.
x=\frac{-8±\sqrt{8^{2}-4\left(-9\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 8 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\left(-9\right)}}{2}
Square 8.
x=\frac{-8±\sqrt{64+36}}{2}
Multiply -4 times -9.
x=\frac{-8±\sqrt{100}}{2}
Add 64 to 36.
x=\frac{-8±10}{2}
Take the square root of 100.
x=\frac{2}{2}
Now solve the equation x=\frac{-8±10}{2} when ± is plus. Add -8 to 10.
x=1
Divide 2 by 2.
x=-\frac{18}{2}
Now solve the equation x=\frac{-8±10}{2} when ± is minus. Subtract 10 from -8.
x=-9
Divide -18 by 2.
x=1 x=-9
The equation is now solved.
x\left(5x-7\right)=\left(x-3\right)\left(4x-3\right)
Variable x cannot be equal to any of the values 0,3 since division by zero is not defined. Multiply both sides of the equation by x\left(x-3\right), the least common multiple of x-3,x.
5x^{2}-7x=\left(x-3\right)\left(4x-3\right)
Use the distributive property to multiply x by 5x-7.
5x^{2}-7x=4x^{2}-15x+9
Use the distributive property to multiply x-3 by 4x-3 and combine like terms.
5x^{2}-7x-4x^{2}=-15x+9
Subtract 4x^{2} from both sides.
x^{2}-7x=-15x+9
Combine 5x^{2} and -4x^{2} to get x^{2}.
x^{2}-7x+15x=9
Add 15x to both sides.
x^{2}+8x=9
Combine -7x and 15x to get 8x.
x^{2}+8x+4^{2}=9+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.
x^{2}+8x+16=9+16
Square 4.
x^{2}+8x+16=25
Add 9 to 16.
\left(x+4\right)^{2}=25
Factor x^{2}+8x+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(x+4\right)^{2}}=\sqrt{25}
Take the square root of both sides of the equation.
x+4=5 x+4=-5
Simplify.
x=1 x=-9
Subtract 4 from both sides of the equation.