Step-by-step explanation:
the numbers : x, y
x + y = 8
x = y - 4
we use the second equation in the first :
y - 4 + y = 8
2y - 4 = 8
2y = 12
y = 6
x = y - 4 = 6 - 4 = 2
I would say B) A parallelogram with all sides equal and all angles equal. Parallelograms aren't all squares. They can be rectangles and rhombuses. I would say B. They all have the same lengths on all sides. They all have the same angles as well. Take a look at the pictures below. They are all parallelograms. All sides are the same, and all angles are the same.
Answer:b
Step-by-step explanation:
You just need to plug those expressions inside the formula: it doesn't matter if they're expressions involving a variable instead of plain numbers: the formula becomes

If you want, you can simplify it by expanding the square and then multiply the two parenthesis:
