Skip to main content
Solve for x
Tick mark Image
Graph

Similar Problems from Web Search

Share

4\left(x^{2}+2\right)+x+7=12+3\left(x^{2}+1\right)
Multiply both sides of the equation by 12, the least common multiple of 3,12,4.
4x^{2}+8+x+7=12+3\left(x^{2}+1\right)
Use the distributive property to multiply 4 by x^{2}+2.
4x^{2}+15+x=12+3\left(x^{2}+1\right)
Add 8 and 7 to get 15.
4x^{2}+15+x=12+3x^{2}+3
Use the distributive property to multiply 3 by x^{2}+1.
4x^{2}+15+x=15+3x^{2}
Add 12 and 3 to get 15.
4x^{2}+15+x-15=3x^{2}
Subtract 15 from both sides.
4x^{2}+x=3x^{2}
Subtract 15 from 15 to get 0.
4x^{2}+x-3x^{2}=0
Subtract 3x^{2} from both sides.
x^{2}+x=0
Combine 4x^{2} and -3x^{2} to get x^{2}.
x\left(x+1\right)=0
Factor out x.
x=0 x=-1
To find equation solutions, solve x=0 and x+1=0.
4\left(x^{2}+2\right)+x+7=12+3\left(x^{2}+1\right)
Multiply both sides of the equation by 12, the least common multiple of 3,12,4.
4x^{2}+8+x+7=12+3\left(x^{2}+1\right)
Use the distributive property to multiply 4 by x^{2}+2.
4x^{2}+15+x=12+3\left(x^{2}+1\right)
Add 8 and 7 to get 15.
4x^{2}+15+x=12+3x^{2}+3
Use the distributive property to multiply 3 by x^{2}+1.
4x^{2}+15+x=15+3x^{2}
Add 12 and 3 to get 15.
4x^{2}+15+x-15=3x^{2}
Subtract 15 from both sides.
4x^{2}+x=3x^{2}
Subtract 15 from 15 to get 0.
4x^{2}+x-3x^{2}=0
Subtract 3x^{2} from both sides.
x^{2}+x=0
Combine 4x^{2} and -3x^{2} to get x^{2}.
x=\frac{-1±\sqrt{1^{2}}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±1}{2}
Take the square root of 1^{2}.
x=\frac{0}{2}
Now solve the equation x=\frac{-1±1}{2} when ± is plus. Add -1 to 1.
x=0
Divide 0 by 2.
x=-\frac{2}{2}
Now solve the equation x=\frac{-1±1}{2} when ± is minus. Subtract 1 from -1.
x=-1
Divide -2 by 2.
x=0 x=-1
The equation is now solved.
4\left(x^{2}+2\right)+x+7=12+3\left(x^{2}+1\right)
Multiply both sides of the equation by 12, the least common multiple of 3,12,4.
4x^{2}+8+x+7=12+3\left(x^{2}+1\right)
Use the distributive property to multiply 4 by x^{2}+2.
4x^{2}+15+x=12+3\left(x^{2}+1\right)
Add 8 and 7 to get 15.
4x^{2}+15+x=12+3x^{2}+3
Use the distributive property to multiply 3 by x^{2}+1.
4x^{2}+15+x=15+3x^{2}
Add 12 and 3 to get 15.
4x^{2}+15+x-15=3x^{2}
Subtract 15 from both sides.
4x^{2}+x=3x^{2}
Subtract 15 from 15 to get 0.
4x^{2}+x-3x^{2}=0
Subtract 3x^{2} from both sides.
x^{2}+x=0
Combine 4x^{2} and -3x^{2} to get x^{2}.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{1}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}+x+\frac{1}{4}. 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+\frac{1}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{1}{2} x+\frac{1}{2}=-\frac{1}{2}
Simplify.
x=0 x=-1
Subtract \frac{1}{2} from both sides of the equation.