The payment with a 6% sales tax is $461.10
Yes it does, it is proportional because it increases by the same amount at a constant time (which is each week's paycheck). The constant is the 150. i may be wrong sorry if so.
(-5,2) concave up
Hope this helps :)
gcf = 3
the factors of 12 are 1, 2, 3, 4, 6 and 12
the factors of 45 are 1, 3, 5, 9, 15 and 45
the greatest common factor of 12 and 45 is 3