
Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion 
 LinkBack  Thread Tools  Display Modes 
February 6th, 2019, 05:53 PM  #1 
Newbie Joined: Jan 2019 From: tornto Posts: 7 Thanks: 0  triangle?
Could not solve this on my exam. Please help with explanation. Thanks. Find the value of x which makes the area of this triangle equal 72. A. x=10.5 B. x=6 C. x=4.6875 D. x=9.375 triangle Last edited by skipjack; February 6th, 2019 at 09:28 PM. 
February 6th, 2019, 07:38 PM  #2 
Newbie Joined: Jan 2019 From: United States Posts: 7 Thanks: 0 
A=(1/2)(b)(h) 72=(1/2)(8)(h) [do keep in mind that h=(2x3)] 72=(4)(h) 18=h Therefore, if h=18 and h=(2x3) then 18=2x3 18=2x3 21=2x 10.5=x Final answer: A 
February 6th, 2019, 09:43 PM  #3 
Global Moderator Joined: Dec 2006 Posts: 20,298 Thanks: 1971 
The triangle can be thought of as the lower left half of a rectangle (with area 72 × 2 = 144). The height of that rectangle (and also the triangle) is therefore 144/8 = 18. Hence 2x  3 = 18, which implies that x = 10.5 (answer A). I've no idea how anyone could arrive at answer C or D. 

Tags 
triangle 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
is orthic triangle same as pedal triangle?  randomgamernerd  Geometry  1  November 16th, 2015 09:09 PM 
in triangle  mared  Geometry  1  June 16th, 2015 10:49 AM 
Triangle ABC  miran97  Algebra  2  March 14th, 2013 08:46 AM 
Moller Triangle to Triangle Collisions  1101  Algebra  0  June 19th, 2009 11:56 PM 
A triangle... Help!  johnnyboy12  Algebra  1  June 8th, 2009 03:41 PM 