The rectangle is 3 times as long as its wide. The area is 56 metre than what is its length ??

Answer 1

length * width = area

3w(w) = 56

w^2 = 56/3

w = sqrt(56/3)

= sqrt( 56*3/ (3*3)) <--- rationalizes the denominator

= sqrt( 56*3) /sqrt(9)

= sqrt( 56*3)/ 3

= sqrt( 2*2*2*3*7) / 3

= 2 * sqrt(2*3*7)/3

= 2 * sqrt(42)/3

which is APPROXIMATELY 4.32049379893857348731+

multiplying by 3 gives the length. Doing so cancels the 3 in the denominator.

So the length is 2 * sqrt(42), which is APPROXIMATELY 12.96148139681572+

So the area is:

2 * Sqrt(42)/3 * 2 * sqrt(42) = 4 * 42/3 = 4 * 14 = 56