Answer:
r = 9
Step-by-step explanation:
Given that c varies directly as (r + 1) then the equation relating them is
c = k(r + 1) ← k is the constant of variation
To find k use the condition c = 8 when r = 3, then
8 = k(3 + 1) = 4k ( divide both sides by 4 )
2 = k
c = 2(r + 1) ← equation of variation
When c = 20, then
20 = 2(r + 1) ← divide both sides by 2
10 = r + 1 ( subtract 1 from both sides )
9 = r
Answer:
b) - 3
Step-by-step explanation:
If x = -3 , then
x + 3 = -3 + 3 = 0
So, denominator would become 0. So , anything divided by 0 is undefined
Time = Distance / speed
Time = 20 miles / 12mph
Time = 1 and 2/3 hours ( 1 hour and 40 minutes)
Answer:
D. 1,211
Step-by-step explanation:
857 + 354 = 1,211 runners
