Question

question 5
quadrilateral a has side lengths of 9, 24, 18, and 12 units. quadrilateral b is a scaled copy of quadrilateral a with its shortest side of length 3 units. what is the perimeter of quadrilateral b?
you can use your dry erase board to help you visualize.
step 1 - divide all lengths of quadrilateral a by 3
step 2 - add all new side lengths to find perimeter.
a 21 units
b 57 units
c 63 units
d 189 units

Explanation:

Step1: Find the scale - factor

The shortest side of Quadrilateral A is 9 units and the shortest side of Quadrilateral B is 3 units. The scale - factor $k=\frac{3}{9}=\frac{1}{3}$.

Step2: Find the side - lengths of Quadrilateral B

Multiply each side - length of Quadrilateral A by the scale - factor.
The new side - lengths are $\frac{9}{3}=3$, $\frac{24}{3}=8$, $\frac{18}{3}=6$, $\frac{12}{3}=4$.

Step3: Calculate the perimeter of Quadrilateral B

The perimeter $P = 3 + 8+6 + 4=21$.

Answer:

A. 21 units