an 8 inch by 12 inch picture has a frame of uniform width around it. the area of the picture and frame is 192 in^2. what is the width of the frame?

Question

this is my problem to solve before i take a quiz and i have no idea how to set it up 

Answer 1

let the uniform width be x inches

length of frame=12+2x   inches

width of frame=8+2x    inches

Area of frame=(12+2x)(8+2x)=192

96+24x+16x+4x^2=192

4x^2+40x-96=0

x^2+10x-24=0

(x+12)(x-2)=0

x=-12 (width cant be negative)

or

x=2

Width of the frame is 2 inches