Answer:
10m
Step-by-step explanation:
<u>Perimeter</u> means adding up all of the sides of a shape.
One property of a square is that <u>all lengths of a square are the same</u>.
We also know squares have <u>4 sides</u>.
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Lets set up an expression to solve the length for each side with variable S representing the length of a side:
4 * S = 40
Divide each side by 4:
S = 10
Therefore, each side of the square has a length 10m
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60 miles in 1 hour (divide the miles by the hours)
Parallel lines never touch they run side by side forever like the rails on railroad tracks
Perpendicular line cross or intersect
Let us draw a picture to make the things more clear.
Attached is the image.
We have been given that

Therefore, we have

Now, in triangle bcd, we have

Now, in triangle acb, we have

Thus, ad is 15 cm.