А-9=75

To solve for 'a' in the equation a - 9 = 75, you have to isolate the variable 'a' on one side of the equation. You do that by performing the opposite operation of what's currently being done to 'a'. Since 9 is being subtracted from 'a', you need to add 9 to both sides of the equation to cancel out the -9 on the left side.

Here's the step-by-step solution:

a - 9 + 9 = 75 + 9 (add 9 to both sides to keep the equation balanced)

Now simplify both sides:

a = 75 + 9 a = 84

The value of 'a' is 84.