High School Math : High School Math
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Example Questions
Example Question #3 : How To Find The Length Of The Diagonal Of A Square
The perimeter of a square is 48. What is the length of its diagonal?
Perimeter = side * 4
48 = side * 4
Side = 12
We can break up the square into two equal right triangles. The diagonal of the sqaure is then the hypotenuse of these two triangles.
Therefore, we can use the Pythagorean Theorem to solve for the diagonal:
Example Question #1 : How To Find The Area Of A Square
ABCD and EFGH are squares such that the perimeter of ABCD is 3 times that of EFGH. If the area of EFGH is 25, what is the area of ABCD?
5
15
225
75
25
225
Assign variables such that
One side of ABCD = a
and One side of EFGH = e
Note that all sides are the same in a square. Since the perimeter is the sum of all sides, according to the question:
4a = 3 x 4e = 12e or a = 3e
From that area of EFGH is 25,
e x e = 25 so e = 5
Substitute a = 3e so a = 15
We aren’t done. Since we were asked for the area of ABCD, this is a x a = 225.
Example Question #611 : Geometry
A square has an area of 36. If all sides are doubled in value, what is the new area?
132
144
108
72
48
144
Let S be the original side length. S*S would represent the original area. Doubling the side length would give you 2S*2S, simplifying to 4*(S*S), giving a new area of 4x the original, or 144.
Example Question #231 : Geometry
If the perimeter of a square is equal to twice its area, what is the length of one of its sides?
Area of a square in terms of each of its sides:
Area = S x S
Perimeter of a square:
Perimeter = 4S
So if 'the perimeter of a square is equal to twice its area':
2 x Area = Perimeter
2 x [S x S] = [4S]; divide by 2:
S x S = 2S; divide by S:
S = 2
Example Question #2 : How To Find The Area Of A Square
Freddie is building a square pen for his pig. He plans to buy x feet of fencing to build the pen. This will result in a pen with an area of p square feet. Unfortunately, he only has enough money to buy one third of the planned amount of fencing. Which expression represents the area of the pen he can build with this limited amount of fencing?
3p
9p
p/9
p/3
p/6
p/9
If Freddie uses x feet of fencing makes a square, each side must be x/4 feet long. The area of this square is (x/4)2 = x2/16 = p square feet.
If Freddie uses one third of x feet of fencing makes a square, each side must be x/12 feet long. The area of this square is (x/12)2 = x2/144 = 1/9(x2/16) = 1/9(p) = p/9 square feet.
Alternate method:
The scale factor between the small perimeter and the larger perimeter = 1 : 3. Since we're comparing area, a two-dimensional measurement, we can square the scale factor and see that the ratio of the areas is 12 : 32 = 1 : 9.
Example Question #212 : Geometry
If the diagonal of a square measures 
This is an isosceles right triangle, so the diagonal must equal 
Example Question #614 : Geometry
A square 
The area of 
Example Question #5 : How To Find The Area Of A Square
The perimeter of a square is 
The perimeter of a square is given by 
So the area of the new square is given by 
Example Question #1 : How To Find The Area Of A Square
How much more area does a square with a side of 2r have than a circle with a radius r? Approximate π by using 22/7.
12/14 square units
1/7 square units
4/7 square units
6/7 square units
6/7 square units
The area of a circle is given by A = πr2 or 22/7r2
The area of a square is given by A = s2 or (2r)2 = 4r2
Then subtract the area of the circle from the area of the square and get 6/7 square units.
Example Question #2 : How To Find The Area Of A Square
If the perimeter of a square is 44 centimeters, what is the area of the square in square centimeters?
Since the square's perimeter is 44, then each side is 
Then in order to find the area, use the definition that the
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