5x+3y=0 -x-2y=7 ____________

5x+3y=0 -x-2y=7 -x-2y=7 x=-2y-7 5x+3y=0 5(-2y-7)+3y=0 3y-10y-35=0 -7y=35 y=-5 x=-2y-7 x=-2*(-5)-7 x=10-7 x=3 odp. x=3; y=-5

5x + 3y = 0 / - (3y) -x - 2y = 7 5x = 3y / ÷ 5 -x - 2y = 7 x = 3y/5 (trzy y nad pięć -x - 2y = 7 x = 3y/5 -(3y/5) - 2y = 7 x = 3y/5 -3y/5 - 2y = 7 / ×5 x = 3y/5 -3y - 2y = 35 x = 3y/5 -5y = 35 / ÷ (-5) x = 3y/5 y = - 7 x= 3 × (-7)/5 y = -7 x = (-21)/5 y = -7 x = -4,2 y = -7

5x+3y=0 -x-2y=7 /*(-1) 5x+3y=0 x+2y+-7 5x+3y=0 x=-7-2y 5(-7-2y)+3y=0 -35-10y+3y=0 -35-7y=0 7y=-35 /:7 y=-5 5x+3*(-5)=0 5x-15=0 5x=15 /:5 x=3 x=3 y=-5