A footpath of uniform width runs around the inside of a rectangular field 12 m long and 14 m wide. If the path occupies 56 m2, the second degree equation from which we can find the width of the path is ______.(Take width = x)
4x2−52x+56=0
Area of outer rectangle =12×14 m2=168 m2
Width of the footpath= x m
Area of inner rectangle=(12−2x)(14−2x) m2=4x2−52x+168 m2
Area of footpath = Area of outer rectangle - Area of inner rectangle
⇒56=168−(4x2−52x+168)
⇒56=168−4x2+52x−168
⇒56=−4x2+52x
⇒4x2−52x+56=0