The sum of Mark's and his Mom's age is 48. His moms age is 3 times his age what is the age of each? ( What are the answer and the equation to this problem??)

In triangle abc, the length of side ab is 12 cm, the length of side bc is 5 cm, and the length of side ca is 9 cm. find the measure of angle a using the law of cosines.

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

What are the domain and range of the function f(x)=2^x+1