SOLUTION: The display area on a cell phone has a 3.5-in. diagonal. a. If the aspect ratio of length to width is 1.5 to 1, determine the length and width of the display area. Round the value

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: The display area on a cell phone has a 3.5-in. diagonal. a. If the aspect ratio of length to width is 1.5 to 1, determine the length and width of the display area. Round the value      Log On


   



Question 1095118: The display area on a cell phone has a 3.5-in. diagonal.
a. If the aspect ratio of length to width is 1.5 to 1, determine the length and width of the display area. Round the values to the nearest hundredth of an inch.
b. If the phone has 326 pixels per inch, approximate the dimensions in pixels.

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
as far as i know, you would solve this as follows:

the diagonal is 3.5 inches.

let x represent the width.
then 1.5 * x represnets the length.

by pythagorus:

(1.5 * x)^2 + x^2 = 3.5^2

simplify to get 1.5^2 * x^2 + x^2 = 3.5^2

factor out the x^2 to get (1.5^2 + 1) * x^2 = 3.5^2

simplify to get 3.25 * x^2 = 12.25

solve for x^2 to get x^2 = 12.25 / 3.25

solve for x to get x = sqrt(12.25 / 3.25)

simplify to get x = 1.941450687.

1.5x is therefore equal to 1.5 * 1.941450687 = 2.91217603

the width is equal to 1.941450687 inches.
the length is equal to 2.91217603 inches.

round these figures to the nearest hundredth of an inch and you get:

the width is equal to 1.94 inches.
the length is equal to 2.91 inches.

if the phone has 326 pixels per inch, then the dimensions of the phone in pixels would be:

length = 2.91 * 326 = 948.66 pixels
width = 1.94 * 326 = 632.44 pixels

this is approximately 949 pixels in length and 632 pixels in width, if you want to round to the nearest whole pixel.