SOLUTION: x^2 + y^2 = 25 y = 5 - x How to solve this?

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Question 1104027: x^2 + y^2 = 25
y = 5 - x
How to solve this?
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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Use the substitution method.


In other words, simply replace y^2 in the first equation with (5-x)^2, based on the second equation .


You will get a single quadratic equation for x:

x^2 + (5-x)^2 = 25.


Simplify and solve for x.


Below is the plot to inspire you:




Plots x^2 + y^2 = 25 (red + green) and y = 5-x (blue)


To see many similar problems solved, look into the lesson
    - Solving systems of algebraic equations of degree 2 and degree 1
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 online textbook under the topic "Systems of equations that are not linear".


Save the link to this online textbook together with its description

Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson

to your archive and use it when it is needed.