Solve for x
x=-100
x=6
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1425+94x+x^{2}=75\times 27
Use the distributive property to multiply 19+x by 75+x and combine like terms.
1425+94x+x^{2}=2025
Multiply 75 and 27 to get 2025.
1425+94x+x^{2}-2025=0
Subtract 2025 from both sides.
-600+94x+x^{2}=0
Subtract 2025 from 1425 to get -600.
x^{2}+94x-600=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.
x=\frac{-94±\sqrt{94^{2}-4\left(-600\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 94 for b, and -600 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-94±\sqrt{8836-4\left(-600\right)}}{2}
Square 94.
x=\frac{-94±\sqrt{8836+2400}}{2}
Multiply -4 times -600.
x=\frac{-94±\sqrt{11236}}{2}
Add 8836 to 2400.
x=\frac{-94±106}{2}
Take the square root of 11236.
x=\frac{12}{2}
Now solve the equation x=\frac{-94±106}{2} when ± is plus. Add -94 to 106.
x=6
Divide 12 by 2.
x=-\frac{200}{2}
Now solve the equation x=\frac{-94±106}{2} when ± is minus. Subtract 106 from -94.
x=-100
Divide -200 by 2.
x=6 x=-100
The equation is now solved.
1425+94x+x^{2}=75\times 27
Use the distributive property to multiply 19+x by 75+x and combine like terms.
1425+94x+x^{2}=2025
Multiply 75 and 27 to get 2025.
94x+x^{2}=2025-1425
Subtract 1425 from both sides.
94x+x^{2}=600
Subtract 1425 from 2025 to get 600.
x^{2}+94x=600
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.
x^{2}+94x+47^{2}=600+47^{2}
Divide 94, the coefficient of the x term, by 2 to get 47. Then add the square of 47 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+94x+2209=600+2209
Square 47.
x^{2}+94x+2209=2809
Add 600 to 2209.
\left(x+47\right)^{2}=2809
Factor x^{2}+94x+2209. 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(x+47\right)^{2}}=\sqrt{2809}
Take the square root of both sides of the equation.
x+47=53 x+47=-53
Simplify.
x=6 x=-100
Subtract 47 from both sides of the equation.
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Simultaneous equation
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Differentiation
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Integration
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Limits
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