a)x/y=0,(6)=6/9=2/3
5x+4y=198
x/2=y/3=k
x=2k
y=3k
10k+12k=198,22k=198,k=198:22
k=9
x=18
y=27
45.x/y=0,(4)=4/9
3x+2y/5x-2y
x/4=y/9=k
x=4k
y=9k
3×4k+2×9k/5×4k-2×9k=
12k+18k/20k-18k=
30k/2k=15
g)x/y=3/7
4x+2y/5x-2y
x/3=y/7=k
x=3k
y=7k
12k+14k/15k-14k=
26k/k=26
