Question #c835c

1 Answer
Jan 18, 2018

The length is 9, and the width is 12.

Explanation:

To understand the math behind us, let's define this problem using mathematical equations:
Area = length x width, or #A = l*w#
And it is given that the ratio of width to length is 3:4, or #3w = 4l#.
Now I am just going to set our given area, 108, to length x width
#108 = l*w#
We can divide by three for our second equation #3w=4l# to get w on its own: #w=(4/3)l#
Now that we have defined #w# in terms of #l#, we can sub it into our first equation:
#108 = l*(4/3)l#, or #108 = (4/3)l^2#.
To solve for l, we first divide by 4/3 and take the square root, giving
#l = 9#. To solve for w now, we can sub our new #l# value into the original equation #108 = l*w#, giving #108=9w#, and when we divide by 9 on both sides we are left with #w = 12#.