SOLUTION: How di identify if 9xsquared+16ysquared=144?

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Question 237434: How di identify if 9xsquared+16ysquared=144?
Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
Steps:
a. Solve for y
b. Substitute this result (in lieu of y) in the original equation
c. If both sides equal, then you know the equation is valid.
Problem:
Step a.
9x%5E2%2B16y%5E2=144
16y%5E2=144-9x%5E2
y%5E2=%28144-9x%5E2%29%2F16
y=sqrt%28%28144-9x%5E2%29%2F%2816%29%29
Step b.
9x%5E2%2B16%28%28sqrt%28144-9x%5E2%2F16%29%29%5E2%29=144
When you elevate a sqrt to the 2nd power, they cancel each other.
%289x%5E2%2B16%28%28144-9x%5E2%29%2F16%29%29=%28144%29
The 16 cancel each other, so:
9x%5E2%2B144-9x%5E2=144
144=144