In this question, it is given that the diagonal of the board is 18 inches long and one side of the board is 12 inches long.
Let the other side is of length b inches .
Now we use pythagorean identity, which is

Here, a = 12 and c=18
Substituting these values, we will get

And the formula of perimeter is

Substituting the values of the two legs, we will get

Answer:
well what line do you have a picture??
Answer:
its C or D
Step-by-step explanation:
i think it's both !
Answer:
The first one: A shape is a rectangle if and only if the shape has exactly four sides and four right angles.
Step-by-step explanation:
The true statement is the first one:
A shape is a rectangle if and only if the shape has exactly four sides and four right angles.