Multiply the equation [tex] x^{2} [/tex] - [tex] y^{2} [/tex] = 5 by -1 then
Add both equation:
( [tex] x^{2} [/tex] + [tex] 2y^{2} [/tex] = 17 )
+( [tex] -x^{2} [/tex] + [tex] y^{2} [/tex] = -5 )
= [tex] 3y^{2} [/tex] =12
= [tex] y^{2} [/tex] = 12/ 3
= [tex] y^{2} [/tex] = 4
[tex] \sqrt{ y^{2} } [/tex] = [tex] \sqrt{4} [/tex]
y = 2
Substitute it to any of the equation:
[tex] x^{2} [/tex] - [tex] y^{2} [/tex] = 5
[tex] x^{2} [/tex] - [tex] 2^{2} [/tex] = 5
[tex] x^{2} [/tex] - 4 = 5
[tex] x^{2} [/tex] = 9
[tex] \sqrt{ x^{2}} [/tex] = [tex] \sqrt{9} [/tex]
x = 3
