The perimeter of a rectangle is 28 inches and the length is 9 inches. what's the area?

To find the area of a rectangle, you must multiply the length and the width.

We are given the length which is 9 inches, now we must find the width.

To find the perimeter, the formula is l + w + l + w = 28. Now we can replace

the l with 9. 9 + w + 9 + w = 28.

We can then find the width.

w + w = 28 - 9 - 9

w + w = 10

w + w = 10

w + w can also be represented as 2w.

2w = 10

w = 10 / 2

w = 5

We now have our length and our width,

l = 9 inches

w = 5 inches

So now we must multiply the two to get the area.

l x w = a

9 x 5 = a

45 = a

And there we have it, your area is 45 inches.

Hope this helps, if my answer or explanation is wrong  

feel free to message me in the comments :).

- genius423

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.