Respuesta :

Answer:

when x = 3, y = 0

when x = -6, y = 27

Step-by-step 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