Question 530090
Hello, 
With this one y2−4x2=19
              9y2+16x2=275
Work with the first equation and set it up as:
y2= 4x^2 + 19
Now substitute this into the second equation:

9(4x^2+19)+16x^2=275 
Expand this out:
36x^2+171+16x^2=275
Combine like terms and subtract 171 to get:
52x^2=104
Divide by 52 to get:
x^2=2
Square root both sides:
x= +-sq rt 2
Plug this into the original equation to get:
y = +-3 sq rt 3
Make sense?
RJ
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