Question

Решить систему
{y=x2-3
{y=2x .

Answer 1

x^2 - 3 =2x
x^2 - 2x - 3 = 0 
D = 4 + 4*3 = 16 = 4^2
x1 = ( 2 + 4)/2 = 6/2 = 3;
x2 = ( 2 - 4)/2 = - 2/2 = - 1;

x1 = 3
y1 = 2*3 = 6;

x2 = - 1
y = 2*(-1) = - 2 

Ответ:
( 3; 6);   ( - 1; - 2)