2(c+4)+5=2c+
(b+15)-7=b+
9a+6-4a=5a+
(p+2.5)+7.5=p+
3(4+n)=3n+
(m+8)+12=m+
6y+18+2y=8(y+)
5(x+2)+3x=8x+
7b+21=7(b+)
4(a+3)=4a+