Question

Решите систему 5(3x-7)-4(2y-3)=20 2x-y-2(y-2)=2

Answer 1

15x-35-8y+12=20
2x-y-2y+4=2
15x-8y=35+20-12
2x-3y=2-4
15x-8y=43
2x-3y=-2
2x=-2+3y
x=(-2+3y)/2
15×(-2+3y)/2-8y=43
-15+22.5y-8y=43
14,5y=43+15
14,5y=58
y=58/14.5
y=4
x=(-2+3×4)/2
x=-5