Yes it is. Input the numbers into the pythagorean theorem,

and if they equal each other it is a right triangle.
Answer:
108
Step-by-step explanation:
Answer:
Two line are perpendicular when they are at right angles to each other.
The red line is perpendicular to the blue line in each of these examples:
Perpendicular Example
Step-by-step ex;planation:
Answer:
11 inches
Step-by-step explanation:
A rectangle's perimeter can be found using:
p=2l+2w
We know that the perimeter, p, is 58, and the length/height is 18. Therefore, we can substitute those values in
58=2(18)+2w
Multiply 2 and 18
58=36+2w
Since we want to find the width, we need to get w by itself. First, subtract 26 from both sides
58-36=36-36+2w
22=2w
Since w is being multiplied by 2, divide both sides by 2. This will cancel out the 2, and leave w by itself.
22/2=2w/2
11=w
So, the width is 11 inches