ok so remember order of simplification PEMDAS parenthaseese exponents multiplicaton or division whichever comes first addition or subtraction whichever comes first
ok so remmeber work from the left to right parenthasees first and work from inside to outer parenthasees
so first one
innermost parenthasees first so first step is 2-4 subtract 4 from 2
second one if xy=0 then assume x and y=0 so (a+2)(b-9)=0 a+2=0 a=-2
b-9=0 b=9
so answe ris a=-2 b=9
third questions
innermost parenthaees first subtract 4 from 2
ok 1. subtrac 4 from 2 2. a=-2, b=9 3. subtract 4 from 2
