Question

решите пожалуйста
завтра сдавать а то времени мало дз много(((

Answer 1

$1.\ left { {{5x-2y=6 atop {7x+2y=6}} right. \ left { {{2y=5x-6 atop {7x+2y=6}} right. \ left { {{2y=5x-6 atop {7x+5x-6=6}} right. \ left { {{2y=5x-6 atop {12x=12} right. \ left { {{2y=5x-6 atop {x=1} right. \ left { {{y=-frac{1}{2}atop {x=1} right.$

$2. \ left { {{x+3y=17} atop {2y-x=13}} right. \ left { {{x=17-3y} atop {2y-x=13}} right. \ left { {{x=17-3y} atop {2y-17+3y=13}} right. \ left { {{x=17-3y} atop {5y=30}} right. \ left { {{x=17-3y} atop {y=6}} right. \ left { {{x=-1} atop {y=6}} right.$

$3. \ left { {{2x-5y=1} atop {4x-5y=7}} right. \ left { {{5y=2x-1} atop {4x-5y=7}} right. \ left { {{5y=2x-1} atop {4x-2x+1=7}} right. \ left { {{y=frac{2}{5}x-frac{1}{5}} atop {2x=6}} right. \ left { {{y=frac{2}{5}*3-frac{1}{5}} atop {x=3}} right. \ left { {{y=1 atop {x=3}} right.$

$4. \ left { {{2y-3x=6} atop {y-3x=9}} right. \ left { {{3x=2y-6} atop {y=9-3x}} right. \ left { {{3x=2y-6} atop {y=9-2y+6}} right. \ left { {{3x=2y-6} atop {3y=15}} right. \ left { {{x=frac{2}{3}y-2} atop {y=5}} right. \ left { {{x=1frac{1}{3} atop {y=5}} right.$

$5. \ left { {{4x-5y=-22} atop {3x+2y=18}} right. \ left { {{5y=4x+22} atop {3x=18-2y}} right. \ left { {{2y=1,6x+8,8} atop {3x=18-2y}} right. \ left { {{2y=1,6x+8,8} atop {3x=18-1,6x-8,8}} right. \ left { {{2y=1,6x+8,8} atop {4,6x=9,2}} right. \ left { {{2y=1,6x+8,8} atop {x=2}} right. \ left { {{2y=3,2+8,8} atop {x=2}} right. \ left { {{2y=12} atop {x=2}} right. \ left { {{y=6} atop {x=2}} right.$