Direct variation is y=kx where k is a constant
the fiest way to see if it is direct or not, is if x increases, then y increases as well,
then we see if y=kx is valid, basically if we have a constant of variation
the first one x increase and y increase
see if same constant
y=kx
-4.5=-3k
1.5=k
so
see next one
-1 and 3
-3=-1(k)
-3=-1(1.5)
-3=-1.5
false
not it
2nd is increase and y decrease, so not direct variation
3rd is x is same but y increase so nope
4th is x increase and y increase, now test the constant
-7.5=-3k
2.5=k
-1 and -2.5
-2.5=-1k
-2.5=-1(2.5)
-2.5=-2.5
true
answer is last option
Answer:
r = - 11
Step-by-step explanation:
Calculate the slope m using the slope formula and equate to - 4
m = 
with (x₁, y₁ ) = (4, 5) and (x₂, y₂ ) = (8, r)
m =
=
= - 4 ( multiply both sides by 4 )
r - 5 = - 16 ( add 5 to both sides )
r = - 11
First blank: 8
Second blank: 5
Third blank: 20
Fourth blank: 60
B. A smaller percentage of second-lunch students (38%) eat outside.
Short Answer D
P(1) = 1(1+1)(2*1 + 1)/6
P(1) = 1(2)(2 +1) / 6
P(1) = 1(2)(3)/6
P(1) = 1
P(2) = 2(2+1)(2*2 + 1) / 6
P(2) = 2(3)(5) / 6
P(2) = 5 So this formula is adding as it goes along. To Find the Total all we need do is use the formula to calculate P(1) to P(7)
P(7) = 7*(7 + 1)(2*7 + 1)/6
P(7) = 7 * 8 * 15 / 6
P(7) = 7 * 4 * 5
P(7) = 140 <<<< Answer