Answer/Step-by-step explanation:
1. x*21 = 24*14 (intersecting chords theorem)
21x = 336
x = 336/21
x = 16
2. 27*x = 45² (secant-tangent rule)
27x = 2,025
x = 2,025/27
x = 75
3. (x + 5)*5 = (4 + 6)*6 (Intersecting secants theorem)
5x + 25 = (10)*6
5x + 25 = 60
5x = 60 - 25
5x = 35
x = 35/5
x = 7
4. (4x + 2)*8 = (5x + 1)*7
32x + 16 = 35x + 7
Collect like terms
32x - 35x = -16 + 7
-3x = -9
x = -9/-3
x = 3