Solve for x
x=1
x=-1
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4+3=7x^{2}
Multiply both sides of the equation by 7.
7=7x^{2}
Add 4 and 3 to get 7.
7x^{2}=7
Swap sides so that all variable terms are on the left hand side.
7x^{2}-7=0
Subtract 7 from both sides.
x^{2}-1=0
Divide both sides by 7.
\left(x-1\right)\left(x+1\right)=0
Consider x^{2}-1. Rewrite x^{2}-1 as x^{2}-1^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=1 x=-1
To find equation solutions, solve x-1=0 and x+1=0.
4+3=7x^{2}
Multiply both sides of the equation by 7.
7=7x^{2}
Add 4 and 3 to get 7.
7x^{2}=7
Swap sides so that all variable terms are on the left hand side.
x^{2}=\frac{7}{7}
Divide both sides by 7.
x^{2}=1
Divide 7 by 7 to get 1.
x=1 x=-1
Take the square root of both sides of the equation.
4+3=7x^{2}
Multiply both sides of the equation by 7.
7=7x^{2}
Add 4 and 3 to get 7.
7x^{2}=7
Swap sides so that all variable terms are on the left hand side.
7x^{2}-7=0
Subtract 7 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 7\left(-7\right)}}{2\times 7}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 7 for a, 0 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 7\left(-7\right)}}{2\times 7}
Square 0.
x=\frac{0±\sqrt{-28\left(-7\right)}}{2\times 7}
Multiply -4 times 7.
x=\frac{0±\sqrt{196}}{2\times 7}
Multiply -28 times -7.
x=\frac{0±14}{2\times 7}
Take the square root of 196.
x=\frac{0±14}{14}
Multiply 2 times 7.
x=1
Now solve the equation x=\frac{0±14}{14} when ± is plus. Divide 14 by 14.
x=-1
Now solve the equation x=\frac{0±14}{14} when ± is minus. Divide -14 by 14.
x=1 x=-1
The equation is now solved.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}