Answer:
4x² -4xy -4y -4
Step-by-step explanation:

In this case, a= 2x -y and b= y +2.
(2x -y)² -(y +2)²
= (2x -y +y +2)[2x -y -(y +2)]
= (2x +2)(2x -y -y -2)
= (2x +2)(2x -2y -2)
= 2x(2x) +2x(-2y) +2x(-2) +2(2x) +2(-2y) +2(-2) <em>(expand)</em>
= 4x² -4xy -4x +4x -4y -4
= 4x² -4xy -4y -4
Alternatively, start by expanding the brackets.


(2x -y)² -(y +2)²
= 4x² -4xy +y² -(y² +4y +4)
= 4x² -4xy +y² -y² -4y -4 <em>(</em><em>expand</em><em>)</em>
= 4x² -4xy -4y -4 <em>(</em><em>simplify</em><em>)</em>
Answer:
The First One
Step-by-step explanation:
Try to substitute x by zero for example
(the minus will gone by zero)
You will get y = +2
and the graph you see the y =+2 !!
I hope that it's a clear solution and explanation.
If we assume that all students who were not sick came then
3/3-1/2=2/3 left
24 were at school
24=2/3 of all
times both sides by 3/2
72/2=all
36=all
there are 36 students
B. might be 4/x=3/4. I'm no mathematician, but if it's wrong, blame my teacher. d would probably be something. I'm no good with numbers.