Geometry Area of a Rhombus Question

LeahC

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Jun 11, 2014
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2
Hello!
My final exam is approaching and as I was going over some problems for review I stumbled upon a few that gave me a significant amount of trouble.

The first reads: Find the area of rhombus PQRS to the nearest tenth. TR=12m I found that each side measured 13 and I began to set up the area formula (A=1/2xd1xd2) however I cannot seem to figure out what the other diagonal is...
problem 1.jpg

The second reads: Find the area of a regular hexagon with perimeter of 72 inches. Round to the nearest tenth. My work is shown in the picture however I am unclear as to how to discover if the triangle is 45, 45, 90 or 30, 60, 90.
problem 2.jpg
Thank you so much!
Leah
 
Hello!
My final exam is approaching and as I was going over some problems for review I stumbled upon a few that gave me a significant amount of trouble.

The first reads: Find the area of rhombus PQRS to the nearest tenth. TR=12m I found that each side measured 13 and I began to set up the area formula (A=1/2xd1xd2) however I cannot seem to figure out what the other diagonal is...
View attachment 4181

The second reads: Find the area of a regular hexagon with perimeter of 72 inches. Round to the nearest tenth. My work is shown in the picture however I am unclear as to how to discover if the triangle is 45, 45, 90 or 30, 60, 90.
View attachment 4182
Thank you so much!
Leah

In problem 1) the diagonals are perpendicular, so you have right triangles. If you know two sides, you can use Pythagoras to solve for the third side.
 
Hello!
My final exam is approaching and as I was going over some problems for review I stumbled upon a few that gave me a significant amount of trouble.

The first reads: Find the area of rhombus PQRS to the nearest tenth. TR=12m I found that each side measured 13 and I began to set up the area formula (A=1/2xd1xd2) however I cannot seem to figure out what the other diagonal is...
View attachment 4181

The second reads: Find the area of a regular hexagon with perimeter of 72 inches. Round to the nearest tenth. My work is shown in the picture however I am unclear as to how to discover if the triangle is 45, 45, 90 or 30, 60, 90.
View attachment 4182
Thank you so much!
Leah

In problem 2) you figured out that each side is 12 by dividing the perimeter (72) by 6. Do the same with the central angle: 360/6 = 60 degrees. Make sense? And all the triangles formed must be isosceles in a regular polygon, so the base angles must be equal. What does that tell you???
 
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