8×6= 8×8= 9×9= 72+5-30=
5×5= 9+17= 5×9= 8×7-12=
90-6= 7×6= 3×8= 8×5+19=
14-7= 50+16= 45+21= 40+20= 78-8=
61-47= 53-5= 2x5= 87+5= 56+8=
35+28+17= 55-9+7= 71-(40+3)= 64-(30-8)=
122=6 486=7×6 38=4×6
+= += +=
×= ×= ×=
我的发现: