Question

The length of a rectangle is 10 cm, which is 1/3 of it's perimeter. Evaluate its perimeter​

Answer 1

Answer:

P = 30cm

Step-by-step explanation:

Solution 1:

If 10 = 1/3P, then P = 10(3).

10(3) = 30.

Solution 2:

Divide the two numbers to find P.

10 ÷ 1/3

becomes 10(3)

And 10(3) is 30.

Solution 3 (involving width):

We know that the formula for a rectangle's perimeter is 2l + 2w.

So we can use this to check later on. Right now, we need to fill out the equation to find the width of a rectangle when length and perimeter* are known.

*Note that if you were starting new, you would need to find the perimeter before doing this.

The formula for finding the width of a rectangle when length and perimeter are known is: $(\frac{1}{2})P - l = w$.

Now insert the known values.

P = 30

l = 10

Now substitute these into the formula.

$(\frac{1}{2})30 - 10 = w$

Now solve (after simplifying).

$15 - 10 = w$

then becomes

$5 = w$

Your width would be 5. Now substitute into the equation for perimeter.

2(10) + 2(5)

becomes

20 + 10

which gives us our answer of 30.

With this, we have our dimensions.

l = 10

w = 5

P = 30

Hope this helps. Have a nice day.

Answer 2

Answer:

Perimeter = 30 cm

Step-by-step explanation:

10 cm x 3 = 30 cm