Question

How do you solve `9a - 8= 73`?

Answer 1

`a=9`

Explanation:

We just need to solve the equation for `a`

`9a-8=73`

Add 8 to both sides:

`9a-8+8=73+8`

`9a=81`

Divide both sides by 9:

`(9a)/9=81/9`

`a=9`

Answer 2

Solution: `a = 9`

Explanation:

Equations should be viewed as logical statements. The equation you give is literally saying that the value of `9a - 8` is exactly equal to the value of `73`.

From this, it follows that we are allowed to make certain manipulations. For example, we can add numbers to both sides of the equation. Doing such yields:

`9a - 8 = 73`,
`9a - 8 (+ 8) = 73 (+ 8)`, (we add `8` to both sides)
`9a = 81`.

We can also divide both sides of the equation by some number, as long as it's the same number. We will divide by `9`.

`9a = 81`,
`(9a)/9 = 81/9`, (we divide both sides by `9`)
`a = 9`.

So our answer is `a = 9`.