91Ó°ÊÓ

Given that $â–\pm ABCD$ and M is the midpoint of $\stackrel{¯}{AB}$. Then prove that $MO=\frac{1}{2}AD$.

In Exercises 5-10 quad. PQRS is a parallelogram. Find the values of a, b, x and y.

The legs of this ironing board are built so that $\mathrm{BO}=\mathrm{AO}=\mathrm{RO}=\mathrm{DO}$.

What theorem guarantees that the board is parallel to the floor $\left(\stackrel{¯}{\mathrm{AR}}âˆ\yen \stackrel{¯}{\mathrm{BD}}\right)$?

Copy the chart. Then place check marks in the appropriate spaces.

Quad WXYZ must be a special figure to meet the conditions stated. Write the best name for that special quadrilateral.

Given that $∠1â‰\dots ∠2â‰\dots ∠3â‰\dots ∠4$. Prove that $EFGH$is a rhombus.

Complete the following statement with the word always, sometimes, or never.

The diagonals of a rectangle are ___ congruent.

For the following figure, complete the statement about the diagram. Then state the definition, postulate or theorem that justify the answer. $m∠1+m∠4=\_\_$

The following figure is rhombus$EFGH$

a. Fbeing equidistant from E and Gmust lie on the __ of$EG$.

b. Hbeing equidistant from E and Gmust lie on the __ of$EG$.

c. From (a) and (b) you can deduce that$\stackrel{¯}{FH}$ is the __ of$EG$.

d. state the theorem of this section that you have just proved.

Must quad. EFGH be a parallelogram? Can it be a parallelogram? Explain.

The quadrilaterals numbered 1, 2, 3, 4, and 5 are parallelograms. If you wanted to show that quadrilateral 6 is also a parallelogram, which of the five methods listed on page 172 would be easiest to use?