Answer
isosceles triangle
Work Step by Step
By using distance formula
RT = $\sqrt (0 - (-a))^{2} + (b-0)^{2}$ = $\sqrt a^{2} + b^{2}$
TS = $\sqrt (a-0)^{2} + (0-b)^{2}$ = $\sqrt a^{2} + b^{2}$
Therefore in triangle RST, RT = TS
therefore triangle ABC is a isosceles triangle
