The distance between two cities is 10km more than one third of the distance between them?
I understand the answer is 15 km - but how do i put the answer in an algebraic equation?
Let be the perimeter of one of the squares (length of one of the pieces of wire).
Its side length is therefore .
Thus its area is
.
Let be the perimeter of the other piece.
Clearly .
Its side length is therefore .
Thus its area is
.
We also know that
Therefore
.
Since you can not have a negative length
.
Remembering that the other length
.
Put this into the calculator and you will know how many cm this length is.