Question 593606
the length equals the monthly growth plus the starting length


a.  L(x) = 1.3x + 20


b.  L(6) = 1.3 * 6 + 20 = 27.8


c.  50 = 1.3x + 20 ___ 30 = 1.3 x ___ 30 / 1.3 = x