Solve for x
x=2
x=37
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374-22x-17x+x^{2}=300
Multiply 22 and 17 to get 374.
374-39x+x^{2}=300
Combine -22x and -17x to get -39x.
374-39x+x^{2}-300=0
Subtract 300 from both sides.
74-39x+x^{2}=0
Subtract 300 from 374 to get 74.
x^{2}-39x+74=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-39 ab=74
To solve the equation, factor x^{2}-39x+74 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,-74 -2,-37
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 74.
-1-74=-75 -2-37=-39
Calculate the sum for each pair.
a=-37 b=-2
The solution is the pair that gives sum -39.
\left(x-37\right)\left(x-2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=37 x=2
To find equation solutions, solve x-37=0 and x-2=0.
374-22x-17x+x^{2}=300
Multiply 22 and 17 to get 374.
374-39x+x^{2}=300
Combine -22x and -17x to get -39x.
374-39x+x^{2}-300=0
Subtract 300 from both sides.
74-39x+x^{2}=0
Subtract 300 from 374 to get 74.
x^{2}-39x+74=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-39 ab=1\times 74=74
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+74. To find a and b, set up a system to be solved.
-1,-74 -2,-37
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 74.
-1-74=-75 -2-37=-39
Calculate the sum for each pair.
a=-37 b=-2
The solution is the pair that gives sum -39.
\left(x^{2}-37x\right)+\left(-2x+74\right)
Rewrite x^{2}-39x+74 as \left(x^{2}-37x\right)+\left(-2x+74\right).
x\left(x-37\right)-2\left(x-37\right)
Factor out x in the first and -2 in the second group.
\left(x-37\right)\left(x-2\right)
Factor out common term x-37 by using distributive property.
x=37 x=2
To find equation solutions, solve x-37=0 and x-2=0.
374-22x-17x+x^{2}=300
Multiply 22 and 17 to get 374.
374-39x+x^{2}=300
Combine -22x and -17x to get -39x.
374-39x+x^{2}-300=0
Subtract 300 from both sides.
74-39x+x^{2}=0
Subtract 300 from 374 to get 74.
x^{2}-39x+74=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(-39\right)±\sqrt{\left(-39\right)^{2}-4\times 74}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -39 for b, and 74 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-39\right)±\sqrt{1521-4\times 74}}{2}
Square -39.
x=\frac{-\left(-39\right)±\sqrt{1521-296}}{2}
Multiply -4 times 74.
x=\frac{-\left(-39\right)±\sqrt{1225}}{2}
Add 1521 to -296.
x=\frac{-\left(-39\right)±35}{2}
Take the square root of 1225.
x=\frac{39±35}{2}
The opposite of -39 is 39.
x=\frac{74}{2}
Now solve the equation x=\frac{39±35}{2} when ± is plus. Add 39 to 35.
x=37
Divide 74 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{39±35}{2} when ± is minus. Subtract 35 from 39.
x=2
Divide 4 by 2.
x=37 x=2
The equation is now solved.
374-22x-17x+x^{2}=300
Multiply 22 and 17 to get 374.
374-39x+x^{2}=300
Combine -22x and -17x to get -39x.
-39x+x^{2}=300-374
Subtract 374 from both sides.
-39x+x^{2}=-74
Subtract 374 from 300 to get -74.
x^{2}-39x=-74
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
x^{2}-39x+\left(-\frac{39}{2}\right)^{2}=-74+\left(-\frac{39}{2}\right)^{2}
Divide -39, the coefficient of the x term, by 2 to get -\frac{39}{2}. Then add the square of -\frac{39}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-39x+\frac{1521}{4}=-74+\frac{1521}{4}
Square -\frac{39}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-39x+\frac{1521}{4}=\frac{1225}{4}
Add -74 to \frac{1521}{4}.
\left(x-\frac{39}{2}\right)^{2}=\frac{1225}{4}
Factor x^{2}-39x+\frac{1521}{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(x-\frac{39}{2}\right)^{2}}=\sqrt{\frac{1225}{4}}
Take the square root of both sides of the equation.
x-\frac{39}{2}=\frac{35}{2} x-\frac{39}{2}=-\frac{35}{2}
Simplify.
x=37 x=2
Add \frac{39}{2} to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
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}