Question

What is the length of AB? A(-1,5), B(2,-4)

Answer 1

3 sqrt(10)

Explanation:

To find the distance, we use the formula

d = sqrt( ( x2-x1)^2 + (y2-y1)^2)

= sqrt( ( 2- -1)^2 + ( -4-5)^2)

= sqrt( (2+1)^2 +(-4-5)^2)

= sqrt( 3^2 +(-9)^2)

= sqrt( 9+81)

= sqrt(90)

= sqrt ( 9*10)

3 sqrt(10)