To calculate the length AF, the length AC is needed. To calculate the length AC, draw the right-angled triangle ABC and label the sides. \(a^2 + b^2 = c^2\) \(\text{BC}^2 + \text{AB}^2 = \text{AC}^ ...

Triangles ABC and GHI are congruent. Triangle GHI is the same as ABC but has been rotated 90° anticlockwise. Triangle DEF is a different size. Image caption, Line segments AB and GH are the same ...