Answer:
slope = 
Step-by-step explanation:
Calculate slope m using the slope formula
m = 
with (x₁, y₁ ) = (0, - 2) and (x₂, y₂ ) = (4, 0) ← 2 points on the line
m =
=
=
= 
Find how many weeks are in a year and times by 5.15
If the bacteria is tripling every 10 minutes, that means the "rate of increase" on that period is 200%, so if say the current amount is "c", 200% of "c" is just 2c, so c + 2c is 3c, a tripled amount.
3a + a - 15 = 225 . your substituting b(a-15) into the first equation. <span />