SOLUTION: A poster is 25 cm taller than it is wide. It is mounted on a piece of cardboard so that there is a 5cm border on all sides. If the area of the boreder is 1350 cm squared what are t

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A poster is 25 cm taller than it is wide. It is mounted on a piece of cardboard so that there is a 5cm border on all sides. If the area of the boreder is 1350 cm squared what are t      Log On


   

Question 255856: A poster is 25 cm taller than it is wide. It is mounted on a piece of cardboard so that there is a 5cm border on all sides. If the area of the boreder is 1350 cm squared what are the dimensions of the poster?
Answer by Greenfinch(383) About Me  (Show Source):
You can put this solution on YOUR website!
Call smaller side x, then larger side is x + 25
small side + border is x + 10 ( border on each side)
large side is x + 35
Area of border is (x + 10)(x + 35) -(x)(x+25) = 1350
Expanding ( x^2 + 45x + 350 ) - (x^2 + 25x) = 1350
20x + 350 = 1350
x = 1000/20 = 50 cm
Check: Picture is 50 x 75 = 3750 cm sq
with border is 60 x 85 = 8100 cm sq
Difference is 1350 cm sq