I NEED HELP WITH THIS EQUATION PROBLEMS.I Don't GET IT.. PLEASE HELP ME You!

1)7-(3-M)+2M

2)2/3a-1/6+1/2a

2)6a-15.3+26.5+25a

1) -(3-m) is really -1(3-M) or -1*3 +(-1)*(-1M); -1*-1 + +1

2)Find a common denominator for 2/3 and 1/2

3) add the coeficients for the a's to get the new coefficient for the a and the numbers to geth the number to get an answer: (6+25)a-26.5-15.3 and simplify.