What is the value of the function f(x) = 3(4 − x) when x = 7? 33 9 –9 –21

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Three times the sum of a number and seven is negative thirty-six. what is the number?

Solve 3x-18=2y and 5x-6y=6 by elimination show work