Answer:
The length of AB is 10.
Explanation:
To find the length of AB, we can imagine the line AB is the hypotenuse of a right triangle, so by using point A and point B to find x and y, we can find the hypotenuse (r).
A = (9,18) --> this means that x = 9, y = 18
B = (1,12) --> this means that x = 1, y = 12
So the change in x is 9-1 = 8 units, and the change in y is 18-12 = 6 units
So the triangle would have x = 8, y = 6.
Using Pythagorean theorem, x²+y²=r² --> so √(x²+y²) = r
√(8² + 6²) = r
r = 10
Therefore the length of AB is 10.