Which equation represents a proportional relationship? 1. y = 7x – 3
2. y = 150x
3. y = 21/x
4. y = 2x + 1

Two cyclists 84 miles apart start riding toward each other at the same. one cycles 2 times as fast as the other. if they meet 4 hours later, what is the speed (in mi/h) of the faster cyclist?

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

52 cm radius = diameter = area = circumference = circumfer