Solve for x
x=7
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x^{2}+49-14x=0
Subtract 14x from both sides.
x^{2}-14x+49=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-14 ab=49
To solve the equation, factor x^{2}-14x+49 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,-49 -7,-7
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 49.
-1-49=-50 -7-7=-14
Calculate the sum for each pair.
a=-7 b=-7
The solution is the pair that gives sum -14.
\left(x-7\right)\left(x-7\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
\left(x-7\right)^{2}
Rewrite as a binomial square.
x=7
To find equation solution, solve x-7=0.
x^{2}+49-14x=0
Subtract 14x from both sides.
x^{2}-14x+49=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-14 ab=1\times 49=49
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+49. To find a and b, set up a system to be solved.
-1,-49 -7,-7
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 49.
-1-49=-50 -7-7=-14
Calculate the sum for each pair.
a=-7 b=-7
The solution is the pair that gives sum -14.
\left(x^{2}-7x\right)+\left(-7x+49\right)
Rewrite x^{2}-14x+49 as \left(x^{2}-7x\right)+\left(-7x+49\right).
x\left(x-7\right)-7\left(x-7\right)
Factor out x in the first and -7 in the second group.
\left(x-7\right)\left(x-7\right)
Factor out common term x-7 by using distributive property.
\left(x-7\right)^{2}
Rewrite as a binomial square.
x=7
To find equation solution, solve x-7=0.
x^{2}+49-14x=0
Subtract 14x from both sides.
x^{2}-14x+49=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-\left(-14\right)±\sqrt{\left(-14\right)^{2}-4\times 49}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -14 for b, and 49 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-14\right)±\sqrt{196-4\times 49}}{2}
Square -14.
x=\frac{-\left(-14\right)±\sqrt{196-196}}{2}
Multiply -4 times 49.
x=\frac{-\left(-14\right)±\sqrt{0}}{2}
Add 196 to -196.
x=-\frac{-14}{2}
Take the square root of 0.
x=\frac{14}{2}
The opposite of -14 is 14.
x=7
Divide 14 by 2.
x^{2}+49-14x=0
Subtract 14x from both sides.
x^{2}-14x=-49
Subtract 49 from both sides. Anything subtracted from zero gives its negation.
x^{2}-14x+\left(-7\right)^{2}=-49+\left(-7\right)^{2}
Divide -14, the coefficient of the x term, by 2 to get -7. Then add the square of -7 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-14x+49=-49+49
Square -7.
x^{2}-14x+49=0
Add -49 to 49.
\left(x-7\right)^{2}=0
Factor x^{2}-14x+49. 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(x-7\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-7=0 x-7=0
Simplify.
x=7 x=7
Add 7 to both sides of the equation.
x=7
The equation is now solved. Solutions are the same.
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Limits
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