Question

quick answer please.... abc is a right triangle. if ac = 4 bc = 10, find ab. leave your answer in simplest radical form

Answer 1

Given that ABC is a right angle triangle And AC=4 and BC=10

So according to pythgoreous theorem:

$AB^2+AC^2=BC^2$

Now put the values in it:

$\begin{gathered} AB^2+(4)^2=(10)^2 \\ AB^2+16=100 \\ AB^2=100-16 \\ AB^2=84 \\ AB=\sqrt[]{84} \\ AB=\sqrt[]{4\times21} \\ AB=2\sqrt[]{21} \end{gathered}$

Hence the correct option is B.