Greeting to you! My name is Cecille and I’m here to answer that question
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Answer:

Step-by-step explanation:
we know that
To find out how much fabric Jen has left for the shorts, subtract the yards of fabric used in her new dress from the total yards of fabric Jen has.
so

Convert mixed number to an improper fraction

substitute

Convert to mixed number

The rectangle is 7 x 4 so the area is 28 sq cm
The triangle has a base of 4 and a height of 3.
The formula is A = 1/2 * b*h
You have 2 triangles so:
2(1/2)*4*3= 12 sq cm
Add together:
28 + 12= 40 sq cm