Help help What is the value of x. Click picture

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

Need on this geometry question. explain how you did it.

Me asap! what is the slope of this line? enter your answer in the box.