The first answer is going to be 15.42 (so b) and the second is going to be 10.67 (so a)
30 + x0.15=y is the first equation
15+x0.20=y is the second equation
Where in both x equals the amount of days it takes and y is your out come
You can solve this problem two ways one by finding the common denominator or just multiply x until you get the same awnser between the both of them
-12 and 18
hope this helps :)
Y intercept is negative 8