To do this let's put 129 where X is, like this: -12(129)+14(129)-6(129)
Now we multiply -12 by 129, which is equal to -1548.
Now we multiply 14 by 129, which is equal to 1806.
Now we multiply -6 by 129, which is equal to -774.
Now, let's put these numbers into an equation, like this: -1548+1806-(-774).
The answer to this equation is 1032.
I hope this helps.
There is only 1 solution for the length of BC.
We can calculate it using Pythagorean theorem.
We can conclude that triangle's hypotenuse is AC.

If that is the case we are looking for a side BC.

Now put in the data.

Hope this helps.
r3t40
Answer:
The length is 72 feet.
Step-by-step explanation:
<em>Equations</em>
2L+2W=192
L=3W
<em>Solving/Substitution</em>
2(3W)+2W=192
8W=192
W=192/8=24
L=24*3=72
The length is 72 feet.
The width is 24 feet.
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