If 2x - 1 =9 , then what is the value of 10x -5 ?
A
45
B
35
C
55
D
95
Correct Answer: 45
2x - 1 = 9 2x = 10 5× 2x = 5× 10 10x = 50 10x - 5 = 50 - 5 = 45