Question

Решить уравнения
А) 3x2-10x+3=0.
Б) 71x2+144x+4=0.
В) 9x2-30x+25=0.

Answer 1

3x²-10x+3= 0;
D = 100 - 4 * 3 * 3 = 100 - 36 = 64

x1 =( 10 - 8)/6 = 2/6 = 1/3

x2 = (10+8)/6 = 3;

71x² + 144x + 4 = 0;

D = 20736 - 4 * 71 * 4 = 20736 - 1136 = 19600

x1= (-144-140)/142 = -2;
x2= (-144+140)/142 = -4/142

9x²-30x+25= 0;

D = 900 - 4 * 9 * 25 = 0;

x1 = 30/18 = 5/3