As attached in the post, what is the area of triangle. Though simple enough, I could not understand the answer to this problem.
Kind please help tell me how do I got about finding the area of the triangle.
Thanks
Area-of-triangle
This topic has expert replies
-
- Master | Next Rank: 500 Posts
- Posts: 431
- Joined: Sat Jan 10, 2009 9:32 am
- Thanked: 16 times
- Followed by:1 members
- Attachments
-
- area-of-triangle.pdf
- (12.25 KiB) Downloaded 129 times
Want to Beat GMAT.
Always do what you're afraid to do. Whoooop GMAT
Always do what you're afraid to do. Whoooop GMAT
- ssmiles08
- Master | Next Rank: 500 Posts
- Posts: 472
- Joined: Sun Mar 29, 2009 6:54 pm
- Thanked: 56 times
If you make 2 more triangles with the diagram, maybe that will help:
you can notice that a side made from P and Q are is a side to another right triangle made by the x and y axis themselves.
the height of this right triangle is 3 (from (0,0) to (0,3))
the base of this right triangle is 4 (from (0,0) to (4,0))
the hypotenuse is 5 which means that side PQ is 5.
Side PR also has a length of 5 b/c you can make a right triangle with base of 3 (from 4,0 to 7,0) and height of 4 (from 7,0 to 7,4)
now we know this is a 45 -45-90
both base and height is 5
so (1/2)(5*5) = 25/2 = 12.5
(A)
you can notice that a side made from P and Q are is a side to another right triangle made by the x and y axis themselves.
the height of this right triangle is 3 (from (0,0) to (0,3))
the base of this right triangle is 4 (from (0,0) to (4,0))
the hypotenuse is 5 which means that side PQ is 5.
Side PR also has a length of 5 b/c you can make a right triangle with base of 3 (from 4,0 to 7,0) and height of 4 (from 7,0 to 7,4)
now we know this is a 45 -45-90
both base and height is 5
so (1/2)(5*5) = 25/2 = 12.5
(A)
-
- Legendary Member
- Posts: 752
- Joined: Sun May 17, 2009 11:04 pm
- Location: Tokyo
- Thanked: 81 times
- GMAT Score:680
if you take the length of the sides of the triangle, it is 5,5,5sqrt(2)
clearly a 45-45-90 triangle
area is (1/2)*5*5
12.5
clearly a 45-45-90 triangle
area is (1/2)*5*5
12.5
The powers of two are bloody impolite!!
- dumb.doofus
- Master | Next Rank: 500 Posts
- Posts: 435
- Joined: Sat Sep 27, 2008 2:02 pm
- Location: San Jose, CA
- Thanked: 43 times
- Followed by:1 members
- GMAT Score:720
Its just the area of the trapezium - area of the two triangles..
i.e. 1/2(3+4)*7 - 12 = 12.5
i.e. 1/2(3+4)*7 - 12 = 12.5
One love, one blood, one life. You got to do what you should.
https://dreambigdreamhigh.blocked/
https://gmattoughies.blocked/
https://dreambigdreamhigh.blocked/
https://gmattoughies.blocked/
-
- Master | Next Rank: 500 Posts
- Posts: 152
- Joined: Wed Mar 12, 2008 4:36 pm
- Thanked: 8 times
- Followed by:2 members
Cant you take the area of a square which is 28 units and subtract the value of the negative space 15.5 around the central triangle for a value of 12.5?
Last edited by artistocrat on Fri Jul 08, 2011 9:13 am, edited 1 time in total.
-
- Legendary Member
- Posts: 752
- Joined: Sun May 17, 2009 11:04 pm
- Location: Tokyo
- Thanked: 81 times
- GMAT Score:680
and how can you be sure that the area of the triangle is half the area of the boxartistocrat wrote:Can't you simply draw a box around the triangle and divide the area of the box by 2. Furthest x coordinate is 7 times greatest y coordinate is 4 equals 28. 28/2=14?
The powers of two are bloody impolite!!
-
- Master | Next Rank: 500 Posts
- Posts: 152
- Joined: Wed Mar 12, 2008 4:36 pm
- Thanked: 8 times
- Followed by:2 members