Question

Look at triangle ABC.

Answer 1

Phyfagorus 

BC^2 + AC^2 = AB^2
BC - 2 units long
AC - 3 units long
2^2 + 3^2 = AB^2
4+9 = AB^2
AB^2 = 13
AB equals square root of ..... :) 

Answer 2

Answer:

Option D is correct.

The length of AB = $\sqrt{13}$ units.

Explanation:

Use Distance(D) formula for two points (x_1 ,y_1) and (x_2 ,y_2) is given by:

$D=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

From the given figure in triangle ABC, A =(4,5) and B= (2,2),

then by using distance formula, we have;

AB =$\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

AB=$\sqrt{(2-4)^2+(2-5)^2}$ or

AB=$\sqrt{(-2)^2+(-3)^2}$

or

AB=$\sqrt{(4+9}$ = $\sqrt{13}$

Therefore, the length of AB = $\sqrt{13}$ unit.