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:
A.
Step-by-step explanation:
In system A, the first equation multiply by 4
8x - 4y = 12 (1st)
3x + 4y = 10 (2nd)
--------------------add
11x = 22
So answer is B.
Answe70
Step-by-step explanation:
Answer: i think its zero
Step-by-step explanation:
or u can just look it up on an sigma math calculator and that should give u the answer