Question

(2х-7)квадрат-11(2х-7)+30=0

Answer 1

(2x-7)² - 11(2x-7) +30 = 0
4x² - 28x + 49 - 22x +77 + 30 = 0 
4x² - 50x +156 = 0 |:2
2x² - 25x + 78= 0
D= 25² - 4*2*78
D= 625-624
D= 1
x1= (25-1)/(2*2)= 6
x2= (25+1)/(2*2)= 6,5
Ответ:6; 6,5