The solution is n = 5 and r = 4
Step-by-step explanation:
Given,
nCr : (n+1)Cr : (n+2)Cr = 1:3:7
To find the value of n and r.
Formula
nCr = [ n! means = n.(n-1).(n-2)....3.2.1]
Now,
nCr : (n+1)Cr = 1:3 and (n+1)Cr : (n+2)Cr = 3:7
or, : = 1:3 or, : =
or, × = or, × =
or, = or, =
or, 3(n+1-r) = n+1 or, 7(n+2-r) = 3(n+2)
or, 3n+3-3r = n+1 or, 7n+14-7r = 3n+6
or, 2n-3r = -2 or, 4n-7r = -8
Now, by solving
2n-3r = -2 -----(1)
4n-7r = -8 -----(2) we will get n and r
Multiplying (1) by and then subtract with (2) we get,
2(2n-3r) - (4n-7r) = -4-(-8)
or, 4n-6r-4n+7r = 4
or, r = 4
From (1) we get,
2n = -2+3(4)
or, 2n = 10
or, n = 5
Hence,
n = 5 and r = 4
Answer:
These slopes are perpendicular
Step-by-step explanation:
y = -1/3 x + 2 ; slope = -1/3
y = 3x - 5; slope = 3
Perpendicular lines, slope is opposite and reciprocal
So answer is perpendicular
Answer:
yes to both
Step-by-step explanation:
For a relationship to be a function then each value of x must relate to exactly one unique value of y.
This is the case in this table as
2 → 76
4 → 152
6 → 228
All unique values thus a function
To determine if it is linear then the rate of change is constant for each set of ordered pairs. This is measured using the slope formula.
m =
with (x₁, y₁ ) = (2, 76) and (x₂, y₂ ) = (4, 152 ) ← ordered pair from table
m = = = 38
Repeat with (x₁, y₁ ) = (4, 152) and (x₂, y₂ ) = (6, 228)
m = = = 38
Since rate of change is constant then function is linear
The pelican is 16 feet ABOVE the water, then dives 20 feet to get to the fish. Basically, just do 20 minus 16, which would be 4 feet. So the pelican is 4 feet below sea level.