2+9= 7+5= 10+8= 6+9=
5+8= 4+8= 16–6= 9–5=
7+8 = 3+7= 9+4= 14+5=
6+8 = 5+9= 9+9= 18–6=
18–7+4= 17+2–6= 18–3–2=
19–5–5= 16–2-1= 3+5+9=