Question

Rezolvati prin metoda reducerii sistemele :

a) { √5x - 3y =8   b) {√3x - √7y = -4
    {√5x - y =6            {2√3x + 3√7y = 27

Answer 1

a)
√5x - 3y =8 |*(-1)
√5x - y =6

-√5x + 3y = -8
√5x - y =6
------------------(+)
2y=-2 => y= -1

√5x - y =6
√5x = 5 => x=√5

b)
√3x - √7y = -4 |*(-2)
2√3x + 3√7y = 27

-2√3x + 2√7y = 8
2√3x + 3√7y = 27
-----------------------(+)
5√7y= 35 => √7y = 7 => y= √7

√3x - √7y = -4
√3x - 7 = -4
√3x = 3 => x= √3