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Magda saw a triangular sign with a base of 4 feet and a height of 2.8 feet. She reasoned that if she first divided each dimension by 2 before multiplying them together, she would get the right area. Is she correct? Explain.

User Zack A
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2 Answers

1 vote

Answer:

No, Magda is incorrect. The actual area is 0.5(4)(2.8) = 5.6 ft2. With Magda's method, the area would be (2)(1.4) = 2.8 ft2.

Explanation:

User Roger Sanders
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6.2k points
7 votes

Answer: She is not correct, because she must multiply the base and the height of the triangle and then divide by 2.

Explanation:

1. The formula for calculate the area of a triangle is shown below:


A=(b*h)/(2)

Where
b is the base and
h is the height.

2. Then, if she applied the method she reasoned, she'd obtain the following area:


b=(4ft)/(2)=2ft\\h=(2.8ft)/(2)=1.4ft\\A=2ft*1.4ft\\A=2.8ft^(2)

3. But actually, Magda should multiply the base and the height of the triangle and then divide by 2. Then, the correct area is:


A=(4ft*2.8ft)/(2)=5.6ft^(2)

User Dmytro Huz
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5.6k points