Question

A rectangular photograph is nine centimeters wide and fourteen centimeters long. The photograph is enlarged by increasing the length and width by an equal amount. If the area of the new photo is 108 square centimeters greater than the area of the original photo, what are the dimensions of the new photo?

Answer 1

Width=13cm

Length=18cm

Explanation:

Width of the Initial Photograph=9cm

Length of the Initial Photograph=14cm

If width and length are increased by an equal amount, say x

New Width=9+x

New Length=14+x

Area of the new photo is 108 square centimeters greater than the area of the original photo.

Area of Original Photo=14*9=126cm²

Aeea of the New Photo=126+108=234cm²

Therefore:

(9+x)(14+x)=234

126+9x+14x+x²-234=0

x²+23x-108=0

x²+27x-4x-108=0

x(x+27)-4(x+27)=0

(x+27)(x-4)=0

x+27=0 or x-4=0

x=-27 or x=4

Since x≠-27

x=4cm

The dimensions of the new photo are:

Width=9+x=9+4=13cm

Length=14+x=14+4=18cm