Skip to main content
Solve for x
Tick mark Image
Graph

Similar Problems from Web Search

Share

15x^{2}+3+7=20
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
15x^{2}+10=20
Add 3 and 7 to get 10.
15x^{2}=20-10
Subtract 10 from both sides.
15x^{2}=10
Subtract 10 from 20 to get 10.
x^{2}=\frac{10}{15}
Divide both sides by 15.
x^{2}=\frac{2}{3}
Reduce the fraction \frac{10}{15} to lowest terms by extracting and canceling out 5.
x=\frac{\sqrt{6}}{3} x=-\frac{\sqrt{6}}{3}
Take the square root of both sides of the equation.
15x^{2}+3+7=20
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
15x^{2}+10=20
Add 3 and 7 to get 10.
15x^{2}+10-20=0
Subtract 20 from both sides.
15x^{2}-10=0
Subtract 20 from 10 to get -10.
x=\frac{0±\sqrt{0^{2}-4\times 15\left(-10\right)}}{2\times 15}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 15 for a, 0 for b, and -10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 15\left(-10\right)}}{2\times 15}
Square 0.
x=\frac{0±\sqrt{-60\left(-10\right)}}{2\times 15}
Multiply -4 times 15.
x=\frac{0±\sqrt{600}}{2\times 15}
Multiply -60 times -10.
x=\frac{0±10\sqrt{6}}{2\times 15}
Take the square root of 600.
x=\frac{0±10\sqrt{6}}{30}
Multiply 2 times 15.
x=\frac{\sqrt{6}}{3}
Now solve the equation x=\frac{0±10\sqrt{6}}{30} when ± is plus.
x=-\frac{\sqrt{6}}{3}
Now solve the equation x=\frac{0±10\sqrt{6}}{30} when ± is minus.
x=\frac{\sqrt{6}}{3} x=-\frac{\sqrt{6}}{3}
The equation is now solved.