Question 438136
Foci are located along the x-axis. ==> semi-major axis = a = 20/2 = 10, and c = 7.
==> {{{b^2 = a^2 - c^2 = 10^2 - 7^2 = 100 - 49 = 51}}}
==> The standard equation is {{{x^2/100 + y^2/51 = 1}}}