1. The problem is to find the sum of the numbers $(-26,9)$ and $(-33)$. 2. First, clarify the notation: $(-26,9)$ appears to be a coordinate or a pair, but since the second number is separated by a comma, it might be a typo or a formatting issue. Assuming the problem is to add $-26.9$ and $-33$ (treating $(-26,9)$ as $-26.9$), we proceed. 3. The formula for addition of two numbers $a$ and $b$ is: $$a + b$$ 4. Substitute the values: $$-26.9 + (-33)$$ 5. Adding two negative numbers means adding their absolute values and keeping the negative sign: $$-(26.9 + 33)$$ 6. Calculate the sum inside the parentheses: $$26.9 + 33 = 59.9$$ 7. So the result is: $$-59.9$$ 8. Therefore, the sum of $-26.9$ and $-33$ is $-59.9$. If the original problem intended something else, please clarify the notation.