Tyler has $4.50 in a bank in his bedroom. Each day he adds $1.50 to it. Which equation can be used to find out how many days it will take for Tyler to save $30.00?

a
4.5 + 1.5x = 30.00
b
(4.5 + 1.5)x = 30.00
c
30.00 + 4.5 = 1.5x
d
4.5 × 1.5 × x = 30.00