SOLUTION: Emily made a sketch of a octagonal window on a 27 in squad piece of paper. First she cut 4 identical isosceles triangles from the corners of the paper. Then she cut a square from t
Algebra.Com
Question 1002922: Emily made a sketch of a octagonal window on a 27 in squad piece of paper. First she cut 4 identical isosceles triangles from the corners of the paper. Then she cut a square from the center of the octagon. Each leg of the cut-off triangle is 1/3 the length of the paper. The side length of the cut-out square is also a 1/3 the length of the paper. What is the area of the sketch after she removed the triangles and the square?
I tried: area of original - area of cut outs
27*27 - 4(27) + 4(9)+
729 - 108 + 36=585
Wrong; the right answer is 486 square inches. How?
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
You forgot about the fact that the triangles have base = height = 9 (since 9 is 1/3 of 27)
Also, the area of the square is not 4*9 it is 9*9
Finally, you don't add in the square cutout. You subtract it off.
-------------------------------------------------------------------------------
Area of paper = s*s = 27*27 = 729
Area of triangles = 4*(b*h)/2 = 4*(9*9)/2 = 162
Area of square cutout = 9*9 = 81
Area of sketch = (Area of paper) - (triangles) - (square cutout)
Area of sketch = (729) - (162) - (81)
Area of sketch = 486 square inches
RELATED QUESTIONS
What is the area of the sketch after she removed the triangles and square? Emily sketched (answered by Alan3354)
Isosceles right triangles are cut from the four corners of a square piece of
paper, 12... (answered by Edwin McCravy)
You fold a large piece of paper in half four times, then unfold it. If you cut along the... (answered by jjordan95)
Please please por favor help me! Im in Honors Geometry and i have no idea how to solve... (answered by richard1234)
a rectangular piece of paper has a length of 25cm and a breadth of 20 cm. The piece of... (answered by josgarithmetic)
A rectangular piece of paper has a width that is 3 inches less than its length. It is cut (answered by Alan3354)
A right pyramid, with a square base and four isosceles triangles, is cut from a square... (answered by solver91311)
Hi
A strip of paper was cut into 2 pieces in the ratio of 1:2. The longer piece was then (answered by Boreal)
How to answer this question, there are 30 players in squad.on a certain day 65 percent of (answered by josgarithmetic)