Solve for v
v=2
v=-2
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7v^{2}+1-29=0
Subtract 29 from both sides.
7v^{2}-28=0
Subtract 29 from 1 to get -28.
v^{2}-4=0
Divide both sides by 7.
\left(v-2\right)\left(v+2\right)=0
Consider v^{2}-4. Rewrite v^{2}-4 as v^{2}-2^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
v=2 v=-2
To find equation solutions, solve v-2=0 and v+2=0.
7v^{2}=29-1
Subtract 1 from both sides.
7v^{2}=28
Subtract 1 from 29 to get 28.
v^{2}=\frac{28}{7}
Divide both sides by 7.
v^{2}=4
Divide 28 by 7 to get 4.
v=2 v=-2
Take the square root of both sides of the equation.
7v^{2}+1-29=0
Subtract 29 from both sides.
7v^{2}-28=0
Subtract 29 from 1 to get -28.
v=\frac{0±\sqrt{0^{2}-4\times 7\left(-28\right)}}{2\times 7}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 7 for a, 0 for b, and -28 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
v=\frac{0±\sqrt{-4\times 7\left(-28\right)}}{2\times 7}
Square 0.
v=\frac{0±\sqrt{-28\left(-28\right)}}{2\times 7}
Multiply -4 times 7.
v=\frac{0±\sqrt{784}}{2\times 7}
Multiply -28 times -28.
v=\frac{0±28}{2\times 7}
Take the square root of 784.
v=\frac{0±28}{14}
Multiply 2 times 7.
v=2
Now solve the equation v=\frac{0±28}{14} when ± is plus. Divide 28 by 14.
v=-2
Now solve the equation v=\frac{0±28}{14} when ± is minus. Divide -28 by 14.
v=2 v=-2
The equation is now solved.
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