Which of the following is a characteristic of all parallelograms?
a. the diagonals bisect each other.
b. both pairs of opposite angles are supplementary.
c. the diagonals are congruent.
d. there are 4 congruent sides.

The base of a triangle exceeds the height by 7 centimeters. if the area is 400 square centimeters, find the length of the base and the height of the triangle.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

Assume that y varies inversely with x. if y=1.6 when x=0.5 find x when y=3.2 acellus answer