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\left(2x\right)^{2}=\left(\sqrt{10+3x}\right)^{2}
Square both sides of the equation.
2^{2}x^{2}=\left(\sqrt{10+3x}\right)^{2}
Expand \left(2x\right)^{2}.
4x^{2}=\left(\sqrt{10+3x}\right)^{2}
Calculate 2 to the power of 2 and get 4.
4x^{2}=10+3x
Calculate \sqrt{10+3x} to the power of 2 and get 10+3x.
4x^{2}-10=3x
Subtract 10 from both sides.
4x^{2}-10-3x=0
Subtract 3x from both sides.
4x^{2}-3x-10=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-3 ab=4\left(-10\right)=-40
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 4x^{2}+ax+bx-10. To find a and b, set up a system to be solved.
1,-40 2,-20 4,-10 5,-8
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 -40.
1-40=-39 2-20=-18 4-10=-6 5-8=-3
Calculate the sum for each pair.
a=-8 b=5
The solution is the pair that gives sum -3.
\left(4x^{2}-8x\right)+\left(5x-10\right)
Rewrite 4x^{2}-3x-10 as \left(4x^{2}-8x\right)+\left(5x-10\right).
4x\left(x-2\right)+5\left(x-2\right)
Factor out 4x in the first and 5 in the second group.
\left(x-2\right)\left(4x+5\right)
Factor out common term x-2 by using distributive property.
x=2 x=-\frac{5}{4}
To find equation solutions, solve x-2=0 and 4x+5=0.
2\times 2=\sqrt{10+3\times 2}
Substitute 2 for x in the equation 2x=\sqrt{10+3x}.
4=4
Simplify. The value x=2 satisfies the equation.
2\left(-\frac{5}{4}\right)=\sqrt{10+3\left(-\frac{5}{4}\right)}
Substitute -\frac{5}{4} for x in the equation 2x=\sqrt{10+3x}.
-\frac{5}{2}=\frac{5}{2}
Simplify. The value x=-\frac{5}{4} does not satisfy the equation because the left and the right hand side have opposite signs.
x=2
Equation 2x=\sqrt{3x+10} has a unique solution.