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Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9

Afunction, f(x), represents the height of a plant x months after being planted. students measure and record the height on a monthly basis. select the appropriate domain for this situation. a. the set of all positive real numbers b. the set of all integers oc. the set of all positive integers od. the set of all real numbers reset next

Solve the following system of equations express your answer as an ordered pair in the format (a, b) with no spaces between the numbers of symbols 5x+2y=22