Question

There are a total of 42 rectangles and pentagons. If you count all vertices, there are 185 vertices. How many rectangles? How many pentagons?

Answer 1

rectangles=25

pentagons=17

Explanation:

let rectangles=x

pentagons=y

no. of vertices of rectangle=4

no. of vertices of pentagon=5

x+y=42

4x+4y=168

4x+5y=185

subtract

y=185-168=17

x=42-17=25