The equation of c is an illustration of subject of formula
The equation of c in terms of r and t is c = r - 15/t
<h3>How to determine the equation?</h3>
The equation is given as:
t = 15/(r - c)
Cross multiply
t(r - c) = 15
Divide both sides by t
r - c = 15/t
Subtract r from both sides
-c = -r + 15/t
Multiply both sides by -1
c = r - 15/t
Take LCM

Hence, the equation of c in terms of r and t is 
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brainly.com/question/10643782
Answer:
a
Step-by-step explanation:
because they spent the least of money on flowers
Let's factor the top and the bottom.
Top factors 4x + 20 = 4(x + 5)
Bottom x^2 + 2x - 15 = (x + 5)(x - 3)
The gcf is the largest value that will go into both the top and the bottom. In our problem the ONLY thing that will go into top and bottom is x + 5 so that is your GCF. (c)
Answer:
9 p.m.
Step-by-step explanation:
Lowest common multiple (LCM) of 6 and 4.
LCM of 6, 4 = 2 × 2 × 3 = 12
After 12 hours 9 A.M. = 9 P.M.
After 12 hours at 9 P.M. she will take both medicines together again.