Hey there! :)
To find out which algebraic expression is equivalent to our given expression, we must simplify everything out.
9(x - 6) + 11(x + 12)
Simplify by using the rainbow method. This just rids us of our parenthesis.
(9 · x) + (9 · -6) + (11 · x) + (11 · 12)
Simplify!
9x + (-54) + 11x + 132
Add like terms.
(9x + 11x) + (-54 + 132)
Simplify.
20x + 78
So, our equivalent equation is C. 20x + 78
~Hope I helped!~