Question

Please help me solve this ​

Answer 1

x=5, y=16

Explanation:

y=x^2-9

y=2x+6

solve by substitution

2x+6= x^2 -9

2x+6 = (x+3) (x-3)

2 (x+3) = (x+3) (x-3)

divide both sides by x+3

2= x-3

add 3 to both sides

x=5

y= 2(5) +6

y= 16

Answer 2

• (-3, 0), (5, 16)

Explanation:

• y = x² - 9
• y = 2x + 6

Solve by substitution:

• x² - 9 = 2x + 6
• x² - 2x - 15 = 0
• x² - 2x + 1 = 16
• (x - 1)² = 4²
• x - 1 = ± 4
• x = 1 ± 4

• x = 5 ⇒ y = 2*5 + 6 = 16
• x = - 3 ⇒ y = 2*(-3) + 6 = 0