512+789=
467*32=
898-512=
267+287=
760*21=
907+401=
9x-7(8-7)=20
2x+7=15
7x+4y=13 5x-2y=19
x+6y=27 7x-3y=9
15960
386
1301
x=3 y=4
x=3 y=-2
1308
x=4
15411
554
x=3
