Help me solve this problem 7 please

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

Brady has a 20 year fixed rate mortgage for $215,500 with monthly payments of 1,305.89.the annual interest rate is 4%. what is the total cost of the principal and interest for this loan rounded to the nearest dollar

What is the correlation coefficient between the variables? round to three decimal places. enter your answer in the box