A rectangular garden plot 16 by 24 meters is to be bordered by a strip of uniform width x meter so as to double the area. Find x.

Answer 1

current area = 16(24) m^2 = 384 m^2

new plot is 16+2x by 24+2x

new area = (16+2x)(24+2x) = 2(384)

expand, simplify to a quadratic equation.
Solve this quadratic using the method you learned.

hint: it factors and has a nice integer solution