Work out the size of angle A

12 point are triangles pqr and stu congruent? what is the congruency that proves they are congruent? what is the perimeter of triangle pqr?

Find the area of the regular hexagon if a side is 20 cm.

What would be the reasons for lines 3 and 4? a. addition property; subtraction property b. addition property; solve c. substitution property; subtraction property d. substitution property; prove