Question

Counting question

Answer 1

@ganeshie8

Answer 2

\(\large \color{black}{\begin{align}
& \normalsize \text{Find the number of rectangles.}\hspace{.33em}\\~\\
\end{align}}\)

Answer 3

the lines are perpendicular to each other.

Answer 4

Begin by choosing two pairs of horizontal lines and two pairs of vertical lines so you can have a rectangle.

Answer 5

I just know theres a ton

Answer 6

Let \(\left(\begin{matrix}a \\ 2\end{matrix}\right)\) be the number of vertical lines that can be picked, and \(\left(\begin{matrix}b \\ 2\end{matrix}\right)\) the number of horizontal lines that can be picked. For each pair of horizontal lines, there's a pair of vertical lines that will form a rectangle with them.
Therefore you have \(\left(\begin{matrix}n \\ 2\end{matrix}\right)\)*\(\left(\begin{matrix}b \\ 2\end{matrix}\right)\) as the number of rectangles.

Answer 7

That would be my guess :)

Answer 8

n=4,b=6 ?

Answer 9

Yes. And sorry, meant to be "a" in the last line.

Answer 10

ok thanks

Answer 11

No problem, do you have an answer to the problem?

Answer 12

no

Answer 13

i m relying on u

Answer 14

All right then!