Write the word sentence as an equation. Then solve. 4 less than a number n is - 15

N - 4 = - 15.

4 less than a number means that 4 is subtracted from a number, n. "Is - 15" means that it is equal to negative 15.

Next all you have to do is solve.

4 less than n is n minus 4

N-4 = - 15

To solve, we move the constants to the other side, isolating n in the process which gives us its value.

The reason this works is because everything is still accounted for, so the answer or value of the equation doesn't change.

To move the constant we have to add 4 to both sides to keep the value the same.

N - 4 + 4 = - 15 + 4

N=-11