Find parallel equation to line y = -5/6 x - 8 with points (3, -6)

For the marigolds:
M= 150 (0.85) ^ x where x is the number of months
For sunflowers:
S= 125- 8x

Part B:
after 3 months there are 150 (0.85) ^3 =92 marigolds

after 3 months there are 123- 8*3 =99 sunflowers

PART C:

there are the same number of plants when the 2 functions are equal

So we have 150 (0.85) ^x =125-8x

They come close to being equal after 2 months and after 14 months