Solve for v
v=-5
v=1
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2v^{2}-10v+44=v^{2}-14v+49
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(v-7\right)^{2}.
2v^{2}-10v+44-v^{2}=-14v+49
Subtract v^{2} from both sides.
v^{2}-10v+44=-14v+49
Combine 2v^{2} and -v^{2} to get v^{2}.
v^{2}-10v+44+14v=49
Add 14v to both sides.
v^{2}+4v+44=49
Combine -10v and 14v to get 4v.
v^{2}+4v+44-49=0
Subtract 49 from both sides.
v^{2}+4v-5=0
Subtract 49 from 44 to get -5.
a+b=4 ab=-5
To solve the equation, factor v^{2}+4v-5 using formula v^{2}+\left(a+b\right)v+ab=\left(v+a\right)\left(v+b\right). To find a and b, set up a system to be solved.
a=-1 b=5
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. The only such pair is the system solution.
\left(v-1\right)\left(v+5\right)
Rewrite factored expression \left(v+a\right)\left(v+b\right) using the obtained values.
v=1 v=-5
To find equation solutions, solve v-1=0 and v+5=0.
2v^{2}-10v+44=v^{2}-14v+49
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(v-7\right)^{2}.
2v^{2}-10v+44-v^{2}=-14v+49
Subtract v^{2} from both sides.
v^{2}-10v+44=-14v+49
Combine 2v^{2} and -v^{2} to get v^{2}.
v^{2}-10v+44+14v=49
Add 14v to both sides.
v^{2}+4v+44=49
Combine -10v and 14v to get 4v.
v^{2}+4v+44-49=0
Subtract 49 from both sides.
v^{2}+4v-5=0
Subtract 49 from 44 to get -5.
a+b=4 ab=1\left(-5\right)=-5
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as v^{2}+av+bv-5. To find a and b, set up a system to be solved.
a=-1 b=5
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. The only such pair is the system solution.
\left(v^{2}-v\right)+\left(5v-5\right)
Rewrite v^{2}+4v-5 as \left(v^{2}-v\right)+\left(5v-5\right).
v\left(v-1\right)+5\left(v-1\right)
Factor out v in the first and 5 in the second group.
\left(v-1\right)\left(v+5\right)
Factor out common term v-1 by using distributive property.
v=1 v=-5
To find equation solutions, solve v-1=0 and v+5=0.
2v^{2}-10v+44=v^{2}-14v+49
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(v-7\right)^{2}.
2v^{2}-10v+44-v^{2}=-14v+49
Subtract v^{2} from both sides.
v^{2}-10v+44=-14v+49
Combine 2v^{2} and -v^{2} to get v^{2}.
v^{2}-10v+44+14v=49
Add 14v to both sides.
v^{2}+4v+44=49
Combine -10v and 14v to get 4v.
v^{2}+4v+44-49=0
Subtract 49 from both sides.
v^{2}+4v-5=0
Subtract 49 from 44 to get -5.
v=\frac{-4±\sqrt{4^{2}-4\left(-5\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 4 for b, and -5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
v=\frac{-4±\sqrt{16-4\left(-5\right)}}{2}
Square 4.
v=\frac{-4±\sqrt{16+20}}{2}
Multiply -4 times -5.
v=\frac{-4±\sqrt{36}}{2}
Add 16 to 20.
v=\frac{-4±6}{2}
Take the square root of 36.
v=\frac{2}{2}
Now solve the equation v=\frac{-4±6}{2} when ± is plus. Add -4 to 6.
v=1
Divide 2 by 2.
v=-\frac{10}{2}
Now solve the equation v=\frac{-4±6}{2} when ± is minus. Subtract 6 from -4.
v=-5
Divide -10 by 2.
v=1 v=-5
The equation is now solved.
2v^{2}-10v+44=v^{2}-14v+49
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(v-7\right)^{2}.
2v^{2}-10v+44-v^{2}=-14v+49
Subtract v^{2} from both sides.
v^{2}-10v+44=-14v+49
Combine 2v^{2} and -v^{2} to get v^{2}.
v^{2}-10v+44+14v=49
Add 14v to both sides.
v^{2}+4v+44=49
Combine -10v and 14v to get 4v.
v^{2}+4v=49-44
Subtract 44 from both sides.
v^{2}+4v=5
Subtract 44 from 49 to get 5.
v^{2}+4v+2^{2}=5+2^{2}
Divide 4, the coefficient of the x term, by 2 to get 2. Then add the square of 2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
v^{2}+4v+4=5+4
Square 2.
v^{2}+4v+4=9
Add 5 to 4.
\left(v+2\right)^{2}=9
Factor v^{2}+4v+4. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(v+2\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
v+2=3 v+2=-3
Simplify.
v=1 v=-5
Subtract 2 from both sides of the equation.
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Limits
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