standard_description: Prove theorems about parallelograms. Theorems include: opposite sides are congruent, opposite angles are congruent, the diagonals of a parallelogram bisect each other, and conversely, rectangles are parallelograms with congruent diagonals.
problem_activity: Evaluate the expressions.
a.
$$24\div(2+1)+(11-8)\times2$$
b.
$$3^2\times4-10+(12-3)^2$$
c.
$$(3\times4)^2-10\times(12-3^2)$$


aligns: no