Solve for x
x = -\frac{10}{7} = -1\frac{3}{7} \approx -1.428571429
x = \frac{10}{7} = 1\frac{3}{7} \approx 1.428571429
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\frac{49}{4}x^{2}-7x+1=-7x+26
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{7}{2}x-1\right)^{2}.
\frac{49}{4}x^{2}-7x+1+7x=26
Add 7x to both sides.
\frac{49}{4}x^{2}+1=26
Combine -7x and 7x to get 0.
\frac{49}{4}x^{2}+1-26=0
Subtract 26 from both sides.
\frac{49}{4}x^{2}-25=0
Subtract 26 from 1 to get -25.
49x^{2}-100=0
Multiply both sides by 4.
\left(7x-10\right)\left(7x+10\right)=0
Consider 49x^{2}-100. Rewrite 49x^{2}-100 as \left(7x\right)^{2}-10^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=\frac{10}{7} x=-\frac{10}{7}
To find equation solutions, solve 7x-10=0 and 7x+10=0.
\frac{49}{4}x^{2}-7x+1=-7x+26
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{7}{2}x-1\right)^{2}.
\frac{49}{4}x^{2}-7x+1+7x=26
Add 7x to both sides.
\frac{49}{4}x^{2}+1=26
Combine -7x and 7x to get 0.
\frac{49}{4}x^{2}=26-1
Subtract 1 from both sides.
\frac{49}{4}x^{2}=25
Subtract 1 from 26 to get 25.
x^{2}=25\times \frac{4}{49}
Multiply both sides by \frac{4}{49}, the reciprocal of \frac{49}{4}.
x^{2}=\frac{100}{49}
Multiply 25 and \frac{4}{49} to get \frac{100}{49}.
x=\frac{10}{7} x=-\frac{10}{7}
Take the square root of both sides of the equation.
\frac{49}{4}x^{2}-7x+1=-7x+26
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{7}{2}x-1\right)^{2}.
\frac{49}{4}x^{2}-7x+1+7x=26
Add 7x to both sides.
\frac{49}{4}x^{2}+1=26
Combine -7x and 7x to get 0.
\frac{49}{4}x^{2}+1-26=0
Subtract 26 from both sides.
\frac{49}{4}x^{2}-25=0
Subtract 26 from 1 to get -25.
x=\frac{0±\sqrt{0^{2}-4\times \frac{49}{4}\left(-25\right)}}{2\times \frac{49}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{49}{4} for a, 0 for b, and -25 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{49}{4}\left(-25\right)}}{2\times \frac{49}{4}}
Square 0.
x=\frac{0±\sqrt{-49\left(-25\right)}}{2\times \frac{49}{4}}
Multiply -4 times \frac{49}{4}.
x=\frac{0±\sqrt{1225}}{2\times \frac{49}{4}}
Multiply -49 times -25.
x=\frac{0±35}{2\times \frac{49}{4}}
Take the square root of 1225.
x=\frac{0±35}{\frac{49}{2}}
Multiply 2 times \frac{49}{4}.
x=\frac{10}{7}
Now solve the equation x=\frac{0±35}{\frac{49}{2}} when ± is plus. Divide 35 by \frac{49}{2} by multiplying 35 by the reciprocal of \frac{49}{2}.
x=-\frac{10}{7}
Now solve the equation x=\frac{0±35}{\frac{49}{2}} when ± is minus. Divide -35 by \frac{49}{2} by multiplying -35 by the reciprocal of \frac{49}{2}.
x=\frac{10}{7} x=-\frac{10}{7}
The equation is now solved.
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