Simplify the expression 2b-3a+b+a

Our goal is to collect email addresses from 60% of customers who purchase a product." so that means if i talk to 95 customers, i need to persuade to provide an email address?

Solve the given system of equations. 2y= -x+9 , 3x-6= -15

Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days