Solve for r
r=-\frac{\sqrt{114}i}{3}\approx -0-3.559026084i
r=\frac{\sqrt{114}i}{3}\approx 3.559026084i
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3r^{2}=-48+10
Add 10 to both sides.
3r^{2}=-38
Add -48 and 10 to get -38.
r^{2}=-\frac{38}{3}
Divide both sides by 3.
r=\frac{\sqrt{114}i}{3} r=-\frac{\sqrt{114}i}{3}
The equation is now solved.
3r^{2}-10+48=0
Add 48 to both sides.
3r^{2}+38=0
Add -10 and 48 to get 38.
r=\frac{0±\sqrt{0^{2}-4\times 3\times 38}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and 38 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
r=\frac{0±\sqrt{-4\times 3\times 38}}{2\times 3}
Square 0.
r=\frac{0±\sqrt{-12\times 38}}{2\times 3}
Multiply -4 times 3.
r=\frac{0±\sqrt{-456}}{2\times 3}
Multiply -12 times 38.
r=\frac{0±2\sqrt{114}i}{2\times 3}
Take the square root of -456.
r=\frac{0±2\sqrt{114}i}{6}
Multiply 2 times 3.
r=\frac{\sqrt{114}i}{3}
Now solve the equation r=\frac{0±2\sqrt{114}i}{6} when ± is plus.
r=-\frac{\sqrt{114}i}{3}
Now solve the equation r=\frac{0±2\sqrt{114}i}{6} when ± is minus.
r=\frac{\sqrt{114}i}{3} r=-\frac{\sqrt{114}i}{3}
The equation is now solved.
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