You have the following algebraic expression:
-6у - 9х - 1 - 3х - у
in order to simplify the previous expression, order like terms first:
-6у - 9х - 1 - 3х - у =
-6y - y - 9x - 3x - 1
next, simplify like terms:
-6y - y - 9x - 3x - 1 =
-7y - 12x - 1
Hence, the simplified expression is -7y - 12x - 1