Solve for y
y = \frac{\sqrt{35}}{5} \approx 1.183215957
y = -\frac{\sqrt{35}}{5} \approx -1.183215957
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5y^{2}=8-1
Subtract 1 from both sides.
5y^{2}=7
Subtract 1 from 8 to get 7.
y^{2}=\frac{7}{5}
Divide both sides by 5.
y=\frac{\sqrt{35}}{5} y=-\frac{\sqrt{35}}{5}
Take the square root of both sides of the equation.
5y^{2}+1-8=0
Subtract 8 from both sides.
5y^{2}-7=0
Subtract 8 from 1 to get -7.
y=\frac{0±\sqrt{0^{2}-4\times 5\left(-7\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
y=\frac{0±\sqrt{-4\times 5\left(-7\right)}}{2\times 5}
Square 0.
y=\frac{0±\sqrt{-20\left(-7\right)}}{2\times 5}
Multiply -4 times 5.
y=\frac{0±\sqrt{140}}{2\times 5}
Multiply -20 times -7.
y=\frac{0±2\sqrt{35}}{2\times 5}
Take the square root of 140.
y=\frac{0±2\sqrt{35}}{10}
Multiply 2 times 5.
y=\frac{\sqrt{35}}{5}
Now solve the equation y=\frac{0±2\sqrt{35}}{10} when ± is plus.
y=-\frac{\sqrt{35}}{5}
Now solve the equation y=\frac{0±2\sqrt{35}}{10} when ± is minus.
y=\frac{\sqrt{35}}{5} y=-\frac{\sqrt{35}}{5}
The equation is now solved.
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Matrix
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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}