SOLUTION: Solve the equations with the quadratic formula x^2+ (7x)^2=25

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Question 1090770: Solve the equations with the quadratic formula
x^2+ (7x)^2=25
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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Solve the equations with the quadratic formula
x^2+ (7x)^2=25
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x^2 + (7x)^2 = 25    is the same as

x^2 + 49x^2 = 25,

50x^2 = 25,

x^2 = 25%2F50,

x^2 = 1%2F2  ====>  x = +/- 1%2Fsqrt%282%29 = +/- sqrt%282%29%2F2.


Answer. The given equation has two solutions:  x= sqrt%282%29%2F2  and  x= -sqrt%282%29%2F2.

I didn't use the quadratic formula, because much simpler solution is enough.


On quadratic formula see the lessons
    - Introduction into Quadratic Equations
    - PROOF of quadratic formula by completing the square
in this site.


Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Quadratic equations".