Answer:
when x = 3, y = 0
when x = -6, y = 27
Explanation:
Rearrange both equations y the subject and then equal to eachother:
y - x² + 9 = 0 ⇒ y = x² - 9
y + 3x - 9 = 0 ⇒ y = 9 - 3x
Therefore, x² - 9 = 9 - 3x
Subtract 9 from both sides: x² - 18 = -3x
Add 3x to both sides: x² + 3x - 18 = 0
Now solve for x:
x² + 3x - 18 = 0
x = 3, x = -6
Substitute values of x found into y = 9 - 3x to find y:
when x = 3, y = 0
when x = -6, y = 27