Ideal for substitution
from the 2nd : x = 3 - 3y
sub into 1st
4(3-3y)^2 + 9y^2 = 36
36 - 72y + 36y^2 + 9y^2 = 36
45y^2 - 72y = 0
5y^2 - 8y = 0
y(5y-8) = 0
y = 0 or y = 8/5
if y = 0 , x = 3
if y = 8/5 , then x = 3-24/5 = -9/5
intersection points (3,0) and (-9/5, 8/5)
Solve using Elimination or Substitution:
4x^2+9y^2=36
x+3y=3
2 answers
Thanks for the help.