Answer:
The width of the rectangle given is equal to 3m.
Step-by-step explanation:
In order to solve this question we need to know that the areas of the rectangle is equal to
, where "l" is length and "w" is width. So know in order to solve this question we would have to find out the unknown width by using area and the length of the triangle. Based on the formula I wrote down earlier we can understand the following.....



Just now we found out the formula that we can use to solve for the width when we know the area and the length of the rectangle. Now in order to get the answer we just have to plug in the values we know, and we get........



The answer would be y=-4x+0
You solve the substitution method to solve a system of equality by expressing one variable in terms of the other using one equation, and then plugging this expression in the other(s).
In this case, the first equation gives us a way to express n in terms of m. So, we can replace every occurrence of n in the second equation with the given formula.
The result is

So, the second equation turned to be an equality, i.e. an equation where both sides are the same.
This implies that the system has infinitely many solutions, because every couple
such that
is a solution to the system, because it satisfies both equations: the first is trivially satisfied, whereas the second is an identity, and as such is satisfied by any value of the variable.