Solve for b
b=\frac{3-\sqrt{1011}}{4}\approx -7.199056548
b = \frac{\sqrt{1011} + 3}{4} \approx 8.699056548
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5^{2}+\left(\frac{25\sqrt{3}}{4}-2\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Multiply \sqrt{3} and \sqrt{3} to get 3.
25+\left(\frac{25\sqrt{3}}{4}-2\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Calculate 5 to the power of 2 and get 25.
25+\left(\frac{17}{4}\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Combine \frac{25\sqrt{3}}{4} and -2\sqrt{3} to get \frac{17}{4}\sqrt{3}.
25+\left(\frac{17}{4}\right)^{2}\left(\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Expand \left(\frac{17}{4}\sqrt{3}\right)^{2}.
25+\frac{289}{16}\left(\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Calculate \frac{17}{4} to the power of 2 and get \frac{289}{16}.
25+\frac{289}{16}\times 3=4^{2}+\left(\frac{3}{4}-b\right)^{2}
The square of \sqrt{3} is 3.
25+\frac{867}{16}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Multiply \frac{289}{16} and 3 to get \frac{867}{16}.
\frac{1267}{16}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Add 25 and \frac{867}{16} to get \frac{1267}{16}.
\frac{1267}{16}=16+\left(\frac{3}{4}-b\right)^{2}
Calculate 4 to the power of 2 and get 16.
\frac{1267}{16}=16+\frac{9}{16}-\frac{3}{2}b+b^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{3}{4}-b\right)^{2}.
\frac{1267}{16}=\frac{265}{16}-\frac{3}{2}b+b^{2}
Add 16 and \frac{9}{16} to get \frac{265}{16}.
\frac{265}{16}-\frac{3}{2}b+b^{2}=\frac{1267}{16}
Swap sides so that all variable terms are on the left hand side.
\frac{265}{16}-\frac{3}{2}b+b^{2}-\frac{1267}{16}=0
Subtract \frac{1267}{16} from both sides.
-\frac{501}{8}-\frac{3}{2}b+b^{2}=0
Subtract \frac{1267}{16} from \frac{265}{16} to get -\frac{501}{8}.
b^{2}-\frac{3}{2}b-\frac{501}{8}=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(-\frac{3}{2}\right)±\sqrt{\left(-\frac{3}{2}\right)^{2}-4\left(-\frac{501}{8}\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -\frac{3}{2} for b, and -\frac{501}{8} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
b=\frac{-\left(-\frac{3}{2}\right)±\sqrt{\frac{9}{4}-4\left(-\frac{501}{8}\right)}}{2}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
b=\frac{-\left(-\frac{3}{2}\right)±\sqrt{\frac{9}{4}+\frac{501}{2}}}{2}
Multiply -4 times -\frac{501}{8}.
b=\frac{-\left(-\frac{3}{2}\right)±\sqrt{\frac{1011}{4}}}{2}
Add \frac{9}{4} to \frac{501}{2} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
b=\frac{-\left(-\frac{3}{2}\right)±\frac{\sqrt{1011}}{2}}{2}
Take the square root of \frac{1011}{4}.
b=\frac{\frac{3}{2}±\frac{\sqrt{1011}}{2}}{2}
The opposite of -\frac{3}{2} is \frac{3}{2}.
b=\frac{\sqrt{1011}+3}{2\times 2}
Now solve the equation b=\frac{\frac{3}{2}±\frac{\sqrt{1011}}{2}}{2} when ± is plus. Add \frac{3}{2} to \frac{\sqrt{1011}}{2}.
b=\frac{\sqrt{1011}+3}{4}
Divide \frac{3+\sqrt{1011}}{2} by 2.
b=\frac{3-\sqrt{1011}}{2\times 2}
Now solve the equation b=\frac{\frac{3}{2}±\frac{\sqrt{1011}}{2}}{2} when ± is minus. Subtract \frac{\sqrt{1011}}{2} from \frac{3}{2}.
b=\frac{3-\sqrt{1011}}{4}
Divide \frac{3-\sqrt{1011}}{2} by 2.
b=\frac{\sqrt{1011}+3}{4} b=\frac{3-\sqrt{1011}}{4}
The equation is now solved.
5^{2}+\left(\frac{25\sqrt{3}}{4}-2\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Multiply \sqrt{3} and \sqrt{3} to get 3.
25+\left(\frac{25\sqrt{3}}{4}-2\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Calculate 5 to the power of 2 and get 25.
25+\left(\frac{17}{4}\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Combine \frac{25\sqrt{3}}{4} and -2\sqrt{3} to get \frac{17}{4}\sqrt{3}.
25+\left(\frac{17}{4}\right)^{2}\left(\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Expand \left(\frac{17}{4}\sqrt{3}\right)^{2}.
25+\frac{289}{16}\left(\sqrt{3}\right)^{2}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Calculate \frac{17}{4} to the power of 2 and get \frac{289}{16}.
25+\frac{289}{16}\times 3=4^{2}+\left(\frac{3}{4}-b\right)^{2}
The square of \sqrt{3} is 3.
25+\frac{867}{16}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Multiply \frac{289}{16} and 3 to get \frac{867}{16}.
\frac{1267}{16}=4^{2}+\left(\frac{3}{4}-b\right)^{2}
Add 25 and \frac{867}{16} to get \frac{1267}{16}.
\frac{1267}{16}=16+\left(\frac{3}{4}-b\right)^{2}
Calculate 4 to the power of 2 and get 16.
\frac{1267}{16}=16+\frac{9}{16}-\frac{3}{2}b+b^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{3}{4}-b\right)^{2}.
\frac{1267}{16}=\frac{265}{16}-\frac{3}{2}b+b^{2}
Add 16 and \frac{9}{16} to get \frac{265}{16}.
\frac{265}{16}-\frac{3}{2}b+b^{2}=\frac{1267}{16}
Swap sides so that all variable terms are on the left hand side.
-\frac{3}{2}b+b^{2}=\frac{1267}{16}-\frac{265}{16}
Subtract \frac{265}{16} from both sides.
-\frac{3}{2}b+b^{2}=\frac{501}{8}
Subtract \frac{265}{16} from \frac{1267}{16} to get \frac{501}{8}.
b^{2}-\frac{3}{2}b=\frac{501}{8}
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.
b^{2}-\frac{3}{2}b+\left(-\frac{3}{4}\right)^{2}=\frac{501}{8}+\left(-\frac{3}{4}\right)^{2}
Divide -\frac{3}{2}, the coefficient of the x term, by 2 to get -\frac{3}{4}. Then add the square of -\frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
b^{2}-\frac{3}{2}b+\frac{9}{16}=\frac{501}{8}+\frac{9}{16}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
b^{2}-\frac{3}{2}b+\frac{9}{16}=\frac{1011}{16}
Add \frac{501}{8} to \frac{9}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(b-\frac{3}{4}\right)^{2}=\frac{1011}{16}
Factor b^{2}-\frac{3}{2}b+\frac{9}{16}. 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-\frac{3}{4}\right)^{2}}=\sqrt{\frac{1011}{16}}
Take the square root of both sides of the equation.
b-\frac{3}{4}=\frac{\sqrt{1011}}{4} b-\frac{3}{4}=-\frac{\sqrt{1011}}{4}
Simplify.
b=\frac{\sqrt{1011}+3}{4} b=\frac{3-\sqrt{1011}}{4}
Add \frac{3}{4} to both sides of the equation.
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