There are x giraffes at the zoo. the number of elephants is 4 less than three times the number of giraffes, and there are more than 23 elephants.

Let X = number of Giraffes
Number of elephants = 3X - 4
Because it was stated that there are more than 23 elephants, the number should not fall below 23.

The algebraic expression would be:

3X - 4 = 23

To get X; Transfer -4 to the other side, changing its sign to positive.

3X = 23 + 4
3X = 27

To get X; Divide both sides by 3
X = 27 / 3
X = 9

Since X represents the number of giraffes, then, there are 9 giraffes in the zoo.

To Check: Substitute X with 9 in the algebraic expression.

3X - 4 = 23
3(9) - 4 = 23
27 - 4 = 23
23 = 23 EQUAL