Answer:
(- 3, - 5 ) , (3, 7 )
Explanation:
Given the 2 equations
y = 2x + 1 → (1)
y = x² + 2x - 8 → (2)
Substitute y = x² + 2x - 8 into (1)
x² + 2x - 8 = 2x + 1 ( subtract 2x + 1 from both sides )
x² - 9 = 0 ( add 9 to both sides )
x² = 9 ( take the square root of both sides )
x = ±
= ± 3
Substitute these values into (1) for corresponding values of y
x = - 3 : y = 2(- 3) + 1 = - 6 + 1 = - 5 ⇒ (- 3, - 5 )
x = 3 : y = 2(3) + 1 = 6 + 1 = 7 ⇒ (3, 7 )