To find the solution to the equation 2x + 5 = 21, we need to isolate the variable x. First, subtract 5 from both sides of the equation:
2x + 5 - 5 = 21 - 5
2x = 16
Then, divide both sides of the equation by 2 to solve for x:
2x / 2 = 16 / 2
x = 8
Therefore, the solution to the equation is x = 8.