2160 - 180 - 432 = 612
Each parallelogram is 3 square inches
divide by 3
612/3 = 264 parallelograms to complete the quilt.
There shouldn't be a negative in front of one of the equations.
ANSWER
The length of the altitude is
units
<u>EXPLANATION</u>
The altitude of a triangle is the vertical height of the triangle.
From the diagram the altitude is 
Method 1: We can use Pythagoras theorem to find 




We take the square root of both sides,




Method 2 Using Trigonometry



