Solve for b
b=6
b=-4
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4+b^{2}-2b+1=29
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(b-1\right)^{2}.
5+b^{2}-2b=29
Add 4 and 1 to get 5.
5+b^{2}-2b-29=0
Subtract 29 from both sides.
-24+b^{2}-2b=0
Subtract 29 from 5 to get -24.
b^{2}-2b-24=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=-24
To solve the equation, factor b^{2}-2b-24 using formula b^{2}+\left(a+b\right)b+ab=\left(b+a\right)\left(b+b\right). To find a and b, set up a system to be solved.
1,-24 2,-12 3,-8 4,-6
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -24.
1-24=-23 2-12=-10 3-8=-5 4-6=-2
Calculate the sum for each pair.
a=-6 b=4
The solution is the pair that gives sum -2.
\left(b-6\right)\left(b+4\right)
Rewrite factored expression \left(b+a\right)\left(b+b\right) using the obtained values.
b=6 b=-4
To find equation solutions, solve b-6=0 and b+4=0.
4+b^{2}-2b+1=29
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(b-1\right)^{2}.
5+b^{2}-2b=29
Add 4 and 1 to get 5.
5+b^{2}-2b-29=0
Subtract 29 from both sides.
-24+b^{2}-2b=0
Subtract 29 from 5 to get -24.
b^{2}-2b-24=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-2 ab=1\left(-24\right)=-24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as b^{2}+ab+bb-24. To find a and b, set up a system to be solved.
1,-24 2,-12 3,-8 4,-6
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -24.
1-24=-23 2-12=-10 3-8=-5 4-6=-2
Calculate the sum for each pair.
a=-6 b=4
The solution is the pair that gives sum -2.
\left(b^{2}-6b\right)+\left(4b-24\right)
Rewrite b^{2}-2b-24 as \left(b^{2}-6b\right)+\left(4b-24\right).
b\left(b-6\right)+4\left(b-6\right)
Factor out b in the first and 4 in the second group.
\left(b-6\right)\left(b+4\right)
Factor out common term b-6 by using distributive property.
b=6 b=-4
To find equation solutions, solve b-6=0 and b+4=0.
4+b^{2}-2b+1=29
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(b-1\right)^{2}.
5+b^{2}-2b=29
Add 4 and 1 to get 5.
5+b^{2}-2b-29=0
Subtract 29 from both sides.
-24+b^{2}-2b=0
Subtract 29 from 5 to get -24.
b^{2}-2b-24=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.
b=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-24\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and -24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
b=\frac{-\left(-2\right)±\sqrt{4-4\left(-24\right)}}{2}
Square -2.
b=\frac{-\left(-2\right)±\sqrt{4+96}}{2}
Multiply -4 times -24.
b=\frac{-\left(-2\right)±\sqrt{100}}{2}
Add 4 to 96.
b=\frac{-\left(-2\right)±10}{2}
Take the square root of 100.
b=\frac{2±10}{2}
The opposite of -2 is 2.
b=\frac{12}{2}
Now solve the equation b=\frac{2±10}{2} when ± is plus. Add 2 to 10.
b=6
Divide 12 by 2.
b=-\frac{8}{2}
Now solve the equation b=\frac{2±10}{2} when ± is minus. Subtract 10 from 2.
b=-4
Divide -8 by 2.
b=6 b=-4
The equation is now solved.
4+b^{2}-2b+1=29
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(b-1\right)^{2}.
5+b^{2}-2b=29
Add 4 and 1 to get 5.
b^{2}-2b=29-5
Subtract 5 from both sides.
b^{2}-2b=24
Subtract 5 from 29 to get 24.
b^{2}-2b+1=24+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
b^{2}-2b+1=25
Add 24 to 1.
\left(b-1\right)^{2}=25
Factor b^{2}-2b+1. 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(b-1\right)^{2}}=\sqrt{25}
Take the square root of both sides of the equation.
b-1=5 b-1=-5
Simplify.
b=6 b=-4
Add 1 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}