Answer:
w=2
Step-by-step explanation:
A=length times width (A=lw)
w= l-3
A=10
Substituting in, we get:
10= l(l-3)
Now, solve the equation.
10= -3l
-3l-10=0
(l+2) (l-5)=0 (factoring the equation)
Therefore, l= -2 or 5
Throw out the negative value because a length of rectangle will never be negative.
Now let's solve for width
Remember w=l-3
therefore
(5)-3=2
so, w=2
(honestly, this is easier to just do in your head. But here is the long form math if you happen to run into more complicated problems.)