Hi i need help with finding the area of a rectangle
sorry this picture is bad but its hard to draw ill explain as best as i can....its a rectangle with a line going diagonly threw it which is equal to 13 and the bottom is base is equal to 12..their is also a right angle symbol at the bottom right
thanks for your help
-----------------------------
[......................... /........]
[............... ./..................]
[........../......13............. ]
[../............................._]
[-------------------------[--]
12
find the area of this rectangle?
2007-12-31 02:40:35 · 6 answers · asked by liz 2 in Science & Mathematics ➔ Mathematics
So Pythagorus can help you find the other side.
13^2 - 12^2 = X^2\
169 - 144 = 25
X = 5
Area = 12 * 5 = 60
2007-12-31 02:52:42 · answer #1 · answered by Robert S 7 · 0⤊ 1⤋
If I understand you correctly, this problem can be solved as follows.
The angle formed by the base and diagonal can be calculated from:
x = acos(12/13)
Then we can calculate the other side length by using:
tan(x) = side/12
So solving....
side = 12*tan(acos(12/13)) = 5
So the area is 5*12 = 60
This could also be done using Pythagoras,
Area = [â(13² - 12²)] * 12 = 60
2007-12-31 03:00:04 · answer #2 · answered by 1,1,2,3,3,4, 5,5,6,6,6, 8,8,8,10 6 · 1⤊ 1⤋
x^2+12^2=13^2
x^2=25
x=5 (width)
5(12)= 60
2007-12-31 02:52:05 · answer #3 · answered by carpe.diem 1 · 0⤊ 1⤋
OK, so as I understand it you have a rectangle with one known side length and one unknown side length. But you are given the length of a line diagonally across the rectangle that bisects the right angles of opposing corners.
This makes it a right triangle. The diagonal line is the hypotenuse. So you can find the other side by using the formula that the sum of the square of the two sides is equal to the square of the hypotenuse.
This tells us the length of the other side is 5. The area is the product of both sides or 60.
2007-12-31 02:51:59 · answer #4 · answered by Anonymous · 0⤊ 1⤋
Before you calculate the area of the rectangle, you have to find the width of the rectangle.
From the given information, you have the diagonal length and the length of the rectangle given; now from Pythagoras theory the width of the rectangle may be calculated. Let the width equals w, then 13^2 = w^2 + 12^2
W^2 = 169-144 = 25
W=5 cm
The area of a rectangle = the length by the width. This is 12*5 = 60 cm^2 or what ever unit of length that you haven't specified!
2007-12-31 02:51:57 · answer #5 · answered by lonelyspirit 5 · 0⤊ 1⤋
You will use Pythagoras to calculate the width .
Width = â( (13)²-(12)²) = 5
Area = Length x width
Area = 12x5 = 60 square unit .
2007-12-31 02:48:37 · answer #6 · answered by Murtaza 6 · 0⤊ 0⤋