Solve for x
x=\frac{\sqrt{3}}{2}\approx 0.866025404
x=-\frac{\sqrt{3}}{2}\approx -0.866025404
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5x\times 4x=3\times 5
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 15x, the least common multiple of 3,5x.
20xx=3\times 5
Multiply 5 and 4 to get 20.
20x^{2}=3\times 5
Multiply x and x to get x^{2}.
20x^{2}=15
Multiply 3 and 5 to get 15.
x^{2}=\frac{15}{20}
Divide both sides by 20.
x^{2}=\frac{3}{4}
Reduce the fraction \frac{15}{20} to lowest terms by extracting and canceling out 5.
x=\frac{\sqrt{3}}{2} x=-\frac{\sqrt{3}}{2}
Take the square root of both sides of the equation.
5x\times 4x=3\times 5
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 15x, the least common multiple of 3,5x.
20xx=3\times 5
Multiply 5 and 4 to get 20.
20x^{2}=3\times 5
Multiply x and x to get x^{2}.
20x^{2}=15
Multiply 3 and 5 to get 15.
20x^{2}-15=0
Subtract 15 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 20\left(-15\right)}}{2\times 20}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 20 for a, 0 for b, and -15 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 20\left(-15\right)}}{2\times 20}
Square 0.
x=\frac{0±\sqrt{-80\left(-15\right)}}{2\times 20}
Multiply -4 times 20.
x=\frac{0±\sqrt{1200}}{2\times 20}
Multiply -80 times -15.
x=\frac{0±20\sqrt{3}}{2\times 20}
Take the square root of 1200.
x=\frac{0±20\sqrt{3}}{40}
Multiply 2 times 20.
x=\frac{\sqrt{3}}{2}
Now solve the equation x=\frac{0±20\sqrt{3}}{40} when ± is plus.
x=-\frac{\sqrt{3}}{2}
Now solve the equation x=\frac{0±20\sqrt{3}}{40} when ± is minus.
x=\frac{\sqrt{3}}{2} x=-\frac{\sqrt{3}}{2}
The equation is now solved.
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