Insert brackets into the following to make them correct
27-4+2²÷4=18
4x2+3-1=19
4=3²+1÷5=6
3+2x6-3=27
7+4-9÷3=8
6÷2+4x2=11
3=1²÷4=4
12+20÷4²=2
7+7-18÷6²=23