Question

David wants to hang a mirror in his room. The mirror and frame must have an area of 8 square feet. The mirror is 2 feet wide and 3 feet long. Which quadratic equation can be used to determine the thickness of the frame, x?

Answer 1

4x^2+10x-2=0

Explanation:

So the total area of mirror: 2*3 = 6 ft sq

8-6 = 2 ft sq is the area of the frame

x is the thickness of the frame

so we have (2*x)*2+(3*x)*2+x*x*4= 2

4x+6x+4x^2=2

-> 4x^2+10x-2=0