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
We have that in this case the following equalities are met:
DH = HF
x + 3 = 3y
GH = HE
3x - 3 = 5y + 4
We then have the following system of equations:
x-3y = -3
3x-5y = 7
Resolving the system graphically we obtain the following values:
x = 9
y = 4
Note: see attached image.
Answer:
The values of x and y are:
x = 9, y = 4