Solve for b
b=6
b=1
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4=\left(\sqrt{3b-2}-\sqrt{10-b}\right)^{2}
Calculate 2 to the power of 2 and get 4.
4=\left(\sqrt{3b-2}\right)^{2}-2\sqrt{3b-2}\sqrt{10-b}+\left(\sqrt{10-b}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\sqrt{3b-2}-\sqrt{10-b}\right)^{2}.
4=3b-2-2\sqrt{3b-2}\sqrt{10-b}+\left(\sqrt{10-b}\right)^{2}
Calculate \sqrt{3b-2} to the power of 2 and get 3b-2.
4=3b-2-2\sqrt{3b-2}\sqrt{10-b}+10-b
Calculate \sqrt{10-b} to the power of 2 and get 10-b.
4=3b+8-2\sqrt{3b-2}\sqrt{10-b}-b
Add -2 and 10 to get 8.
4=2b+8-2\sqrt{3b-2}\sqrt{10-b}
Combine 3b and -b to get 2b.
2b+8-2\sqrt{3b-2}\sqrt{10-b}=4
Swap sides so that all variable terms are on the left hand side.
2b-2\sqrt{3b-2}\sqrt{10-b}=4-8
Subtract 8 from both sides.
2b-2\sqrt{3b-2}\sqrt{10-b}=-4
Subtract 8 from 4 to get -4.
-2\sqrt{3b-2}\sqrt{10-b}=-4-2b
Subtract 2b from both sides of the equation.
\left(-2\sqrt{3b-2}\sqrt{10-b}\right)^{2}=\left(-2b-4\right)^{2}
Square both sides of the equation.
\left(-2\right)^{2}\left(\sqrt{3b-2}\right)^{2}\left(\sqrt{10-b}\right)^{2}=\left(-2b-4\right)^{2}
Expand \left(-2\sqrt{3b-2}\sqrt{10-b}\right)^{2}.
4\left(\sqrt{3b-2}\right)^{2}\left(\sqrt{10-b}\right)^{2}=\left(-2b-4\right)^{2}
Calculate -2 to the power of 2 and get 4.
4\left(3b-2\right)\left(\sqrt{10-b}\right)^{2}=\left(-2b-4\right)^{2}
Calculate \sqrt{3b-2} to the power of 2 and get 3b-2.
4\left(3b-2\right)\left(10-b\right)=\left(-2b-4\right)^{2}
Calculate \sqrt{10-b} to the power of 2 and get 10-b.
\left(12b-8\right)\left(10-b\right)=\left(-2b-4\right)^{2}
Use the distributive property to multiply 4 by 3b-2.
128b-12b^{2}-80=\left(-2b-4\right)^{2}
Use the distributive property to multiply 12b-8 by 10-b and combine like terms.
128b-12b^{2}-80=4b^{2}+16b+16
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(-2b-4\right)^{2}.
128b-12b^{2}-80-4b^{2}=16b+16
Subtract 4b^{2} from both sides.
128b-16b^{2}-80=16b+16
Combine -12b^{2} and -4b^{2} to get -16b^{2}.
128b-16b^{2}-80-16b=16
Subtract 16b from both sides.
112b-16b^{2}-80=16
Combine 128b and -16b to get 112b.
112b-16b^{2}-80-16=0
Subtract 16 from both sides.
112b-16b^{2}-96=0
Subtract 16 from -80 to get -96.
-16b^{2}+112b-96=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{-112±\sqrt{112^{2}-4\left(-16\right)\left(-96\right)}}{2\left(-16\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -16 for a, 112 for b, and -96 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
b=\frac{-112±\sqrt{12544-4\left(-16\right)\left(-96\right)}}{2\left(-16\right)}
Square 112.
b=\frac{-112±\sqrt{12544+64\left(-96\right)}}{2\left(-16\right)}
Multiply -4 times -16.
b=\frac{-112±\sqrt{12544-6144}}{2\left(-16\right)}
Multiply 64 times -96.
b=\frac{-112±\sqrt{6400}}{2\left(-16\right)}
Add 12544 to -6144.
b=\frac{-112±80}{2\left(-16\right)}
Take the square root of 6400.
b=\frac{-112±80}{-32}
Multiply 2 times -16.
b=-\frac{32}{-32}
Now solve the equation b=\frac{-112±80}{-32} when ± is plus. Add -112 to 80.
b=1
Divide -32 by -32.
b=-\frac{192}{-32}
Now solve the equation b=\frac{-112±80}{-32} when ± is minus. Subtract 80 from -112.
b=6
Divide -192 by -32.
b=1 b=6
The equation is now solved.
2^{2}=\left(\sqrt{3\times 1-2}-\sqrt{10-1}\right)^{2}
Substitute 1 for b in the equation 2^{2}=\left(\sqrt{3b-2}-\sqrt{10-b}\right)^{2}.
4=4
Simplify. The value b=1 satisfies the equation.
2^{2}=\left(\sqrt{3\times 6-2}-\sqrt{10-6}\right)^{2}
Substitute 6 for b in the equation 2^{2}=\left(\sqrt{3b-2}-\sqrt{10-b}\right)^{2}.
4=4
Simplify. The value b=6 satisfies the equation.
b=1 b=6
List all solutions of -2\sqrt{10-b}\sqrt{3b-2}=-2b-4.
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