x^2+(x-3)^2=15^2 решите

х² + (х - 3)² = 15²

х² + х² - 6х + 9 = 225

2х² - 6х + 9 = 225

2х² - 6х + 9 - 225 = 0

2х² - 6х - 216 = 0

х² - 3х - 108 = 0

х² + 9х - 12х - 108 = 0

х(х + 9) - 12(х + 9) = 0

(х + 9) ( х - 12) = 0

х + 9 = 0

х - 12 = 0

х1 = - 9, х2 = 12