Answer:
A=147 units²
Step-by-step explanation:
Area for rectangle is A=bh (base x height)
Knowing that, we can substitute what we know. So we know that b=3h (3 times the length of the other side), however we also know that b-h=14 (difference between the two is 14).
Let's solve so that we get b by itself for the second equation
b-h=14
b=h+14
Now we have b=3h and b=h+14. We can have them equal each other since they both equal b.
3h=h+14
2h=14
h=7
Now let's go back and plug into b if we know h=7.
b=3h
b=3(7)
b=21
Now we know h=7 and b=21, so let's plug that into the area for a rectangle which is A=bh
A=bh
A=(21)(7)
A=147 units²
