Which one of these is a right-angled isosceles triangle?
| A. |  |
B. |  |
C. |  |
D. |  |
Show Worked Solution
\(\text{Isosceles triangle had 2 sides the same length.}\)
\(\text{Right-angled triangle has one angle equal to 90°.}\)
| \(\text{Unknown angle}\) | \(= 180-(45 + 45)\) |
| \(= 90^{\circ}\) |
\(\Rightarrow D\)