Question

Find the dimensions of a rectangle whose perimeter is 42 m and whose area is 104 m^2

Answer 1

2x+2y = 42

xy=104

Answer 2

simultaneous eqns

Answer 3

x=length , y =width

Answer 4

Let x,y be length and width of rectangle
2x+2y = 42
xy = 104

solve system using substitution
2y = 42-2x
y = 21 -x
x(21-x) = 104
21x - x^2 = 104
x^2 -21x +104 = 0
(x-13)(x-8)=0
x=8 or x=13

dimensions are 8 and 13