PLEASE HELP Look at the triangle ABC.
A (4.5)
5
4
3
2
1
C (4.1)
B (2.1)
1 2 3
4 5
--5 -4 -3 -2 -1 0
-1
-2
-3
-4
-5
What is the length of the side AB of the triangle?
2
20
38

Explanation:

Count out the spaces, or use subtraction, to find the horizontal side BC is 2 units long. Similarly, you'll find the vertical side AC is 4 units long.

Use the pythagorean theorem to find the length of segment AB.

a^2 + b^2 = c^2

2^2 + 4^2 = c^2

4 + 16 = c^2

20 = c^2

c^2 = 20

c = sqrt(20)

We stop here since it matches with choice B.

Optionally, we can simplify like so

sqrt(20) = sqrt(4*5)

sqrt(20) = sqrt(4)*sqrt(5)

sqrt(20) = 2*sqrt(5)