2012 · Q71
In the figure, angles x degrees, a degrees, c degrees and (pi - b) degrees are indicated (D-C and E-B are drawn segments, A-B-C collinear, A-D-E collinear). Which one of the following is correct?
Elementary MathematicsGeometry
- Ax = a + c - b
- Bx = b - a - c
- Cx = a + b + c
- Dx = a - b + c
Explanation
In triangle BFC, angle FBC = 180-a-b; then in triangle ABE, exterior angle x = c + (a+b).