Question

Pretty Please help with a cherry on top, Don't understand this at all will fan and medal. What is the side length of a square with an area of 225 cm2?
Use an appropriate technique to solve.

A.
112.5 cm

B.
15 cm

C.
56.25 cm

D.
45 cm

Answer 1

Area of a rectangle is given by length time width: \(\large\rm A=\ell\cdot w\)
If we have a square, then the length and width are the same: \(\large\rm A=\ell\cdot\ell\)

We can write the length times length as length squared: \(\large\rm A=\ell^2\)
They gave us the value of the area, so we can plug it in,
\(\large\rm 225=\ell^2\)

Answer 2

So to solve for the side length l, we need to "undo" the squaring on it.

Answer 3

Do you remember how to undo "squaring"?

Hint:
we undo `multiplication` with `division`
we undo `addition` with `subtraction`
we undo `square` with ?

Answer 4

i don't know how to do squaring

Answer 5

Anyway, you undo `squaring` with `square root`.
Applying square root to each side gives us,\[\large\rm \sqrt{225}=\sqrt{\ell^2}\]The square root and square undo one another, giving us our side length.\[\large\rm \sqrt{225}=\ell\]

And then you'll have to uh, simply a little bit from there.