You are here:

Advanced Math/Dimensions Follow-up

Advertisement


Question
I am not clear on this part of your solution:


dimensions of picture: (L-4) inches by (W-4) inches
area of picture = (L-4)(W-4) = LW - 4W - 4L + 16 inē

LW - (LW - 4W - 4L + 16) = 152
4W + 4L = 168
W + L = 42"

Thanks again.

Answer
L and W are the dimensions of the whole thing, i.e., picture surrounded by frame.

The horizontal width of the picture is W - left frame - right frame = W - 2 - 2 = W - 4 inches:
https://www.flickr.com/photos/dwread/14139979715/

Similarly, the vertical length of the picture is L - frame above - frame below = L - 2 - 2 = L - 4 inches.
Therefore, the area of the picture is (L-4)(W-4) inē.

area of frame = combined area of picture and frame - area of picture
152 inē = LW - (L-4)(W-4)
This reduces to
W + L = 42 in

Since the length is twice the width,
W = 14 in
L = 28 in

Advanced Math

All Answers


Answers by Expert:


Ask Experts

Volunteer


Janet Yang

Expertise

I can answer questions in Algebra, Basic Math, Calculus, Differential Equations, Geometry, Number Theory, and Word Problems. I would not feel comfortable answering questions in Probability and Statistics or Topology because I have not studied these in depth.

Experience

I tutor students (fifth through twelfth grades) and am a Top Contributor on Yahoo!Answers with over 24,000 math solutions.

Publications
Co-author of An Outline of Scientific Writing: For Researchers With English as a Foreign Language

Education/Credentials
I have a Bachelor's degree in Applied Mathematics from the University of California at Berkeley.

Past/Present Clients
George White Elementary School. Homework Help program at the Ridgewood Public Library, Ridgewood, NJ. Individual students.

©2016 About.com. All rights reserved.