Solve for x
x=\sqrt{7}\approx 2.645751311
x=-\sqrt{7}\approx -2.645751311
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x^{2}=3+4
Add 4 to both sides.
x^{2}=7
Add 3 and 4 to get 7.
x=\sqrt{7} x=-\sqrt{7}
Take the square root of both sides of the equation.
x^{2}-4-3=0
Subtract 3 from both sides.
x^{2}-7=0
Subtract 3 from -4 to get -7.
x=\frac{0±\sqrt{0^{2}-4\left(-7\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 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\left(-7\right)}}{2}
Square 0.
x=\frac{0±\sqrt{28}}{2}
Multiply -4 times -7.
x=\frac{0±2\sqrt{7}}{2}
Take the square root of 28.
x=\sqrt{7}
Now solve the equation x=\frac{0±2\sqrt{7}}{2} when ± is plus.
x=-\sqrt{7}
Now solve the equation x=\frac{0±2\sqrt{7}}{2} when ± is minus.
x=\sqrt{7} x=-\sqrt{7}
The equation is now solved.
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