Question

решите а,б,в 8 класс.

Answer 1

а) 5x²+8x-4 = 0

D = 64+4*5*4 = 144 = (12)²

x1 = (-8-12)/10 = -20/10 = -2

x2 = (-8+12)/10 = 4/10 = 0,4

б) 25x²-4 = 0

(5x-2)(5x+2) = 0

x1 = 2/5 = 0,4

x2 = -2/5 = -0,4

в) 6x² = 18x

6x²-18x = 0

6x(x-3) = 0

x1 = 0

x2 = 3