Question

Tolong bantu yang latihan 7.2 dong makasih :)

Answer 1

(60 - x)(30 - x) = 1000
1800 - 90x + x² = 1000
x² - 90x + 1800 - 1000 = 0
x² - 90x + 800 = 0
(x - 80)(x - 10) = 0
x = 80
x = 10 

semoga membantu :)