Someone please help me thank you

Question

asked Jan 1, 2022 228k views

2 Answers

Maloo · Answer 1 · 2022-01-07T07:54:21+0000

Answer:

4

Explanation:

7x = x² - 8

=> x² - 7x - 8 = 0

use quadratic formula:

a = 1, b = -7, c = -8

x =
$\frac{-(1)±\sqrt{(-7)^(2) - 4(1)(-8) } }{2(1)}$ (pls ignore the "A" I don't know why it's showing up)

=> x =
(-1±√(49 + 32) )/(2)

=> x =
(-1±9 )/(2)

=> x =
(-1 +9)/(2) = 4 or
(-1-9)/(2) = -5 (the answer is only 4 since it's asking for the positive solution)