The number of students at a school decreased 20% from 2010 to 2011. If the number of students enrolled in 2011 was k, which of the following expresses the number of students enrolled in 2010
in terms of k?
A) 0.75k
B) 1.20%
C) 1.25K
D) 1.5k

C

Step-by-step explanation:

Okay, here we have a reduction in the number of students by 20% from 2010 to 2011.

In 2011, we had k students, so we want to calculate the number of students we had in 2010.

Let the number of students present in 2010 be x

So mathematically;

x - 20% of x = k

x - 0.2(x) = k

0.8x = k

x = k/0.8

x = k * 1/0.8

x = k * 1.25

x = 1.25k

to plot points   for x just start at the origin (middle) and go to the left however many times it say(if the number is a positive) if the number is a negative then go right however many times it says if it is 0 go nowhere

now keep you pencil there and go up however many times it says on y(if it is positive) if it is negative then go down however many times it says. if it says 0 go nowhere.

you have just plotted a point! now when you finish plotting all of them connect them with a ruler

plot each point as (-3, 7), (0,4), (3,1), (8,-4)   in the parenthesis on the left of the comma is x and the right is y.

a) y = -3x +2

b) y = 1/2x -6

these 2 can be combined into one equation.

-3x +2 = .5x -6

8 = 3.5x

x = 8 / 3.5 = 2.2857142857

y = -3 * (8 / 3.5) +2

y = (-24 / 3.5) + 2

y = -4.8571428571

step-by-step explanation: