Solve for x
x=-30
x=0
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x\left(x+5\times 6\right)=0
Factor out x.
x=0 x=-30
To find equation solutions, solve x=0 and x+30=0.
x^{2}+30x=0
Multiply 5 and 6 to get 30.
x=\frac{-30±\sqrt{30^{2}}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 30 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-30±30}{2}
Take the square root of 30^{2}.
x=\frac{0}{2}
Now solve the equation x=\frac{-30±30}{2} when ± is plus. Add -30 to 30.
x=0
Divide 0 by 2.
x=-\frac{60}{2}
Now solve the equation x=\frac{-30±30}{2} when ± is minus. Subtract 30 from -30.
x=-30
Divide -60 by 2.
x=0 x=-30
The equation is now solved.
x^{2}+30x=0
Multiply 5 and 6 to get 30.
x^{2}+30x+15^{2}=15^{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
Square 15.
\left(x+15\right)^{2}=225
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{225}
Take the square root of both sides of the equation.
x+15=15 x+15=-15
Simplify.
x=0 x=-30
Subtract 15 from both sides of the equation.
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