Question

2a-1=19 solve. two step equation

Answer 1

2a - 1 = 19...add 1 to both sides
2a - 1 + 1 = 19 + 1....simplify
2a = 20...divide both sides by 2
(2/2)a = 20/2
1a (or just a) = 10

Answer 2

2a - 1 = 19
2a = 20
a = 10