You would subtract x from each side. It would then be 3y=-x-15. Then you would divide all of the equation by 3. Your final answer would be y=-3x-5.
The mean is the average of a set of numbers.
To find the mean of this data, form a number set by gathering all the numbers.
We need to find the average weekly allowance. To do this, each number in the number set should be the different allowances, and their quantity is the number of students who earned that allowance.
In this case, there would be seven 0s, five 3s, seven 5s, three 6s, and two 8s.
The numbers are:
0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 8, 8
To find the mean of these numbers, add then together then divide by the total amount of numbers.
This means doing:
(0 + 0 + 0 + 0 + 0 + 0 + 0 + 3 + 3 + 3 + 3 + 3 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 6 + 6 + 6 + 8 + 8) / 7 + 5 + 7 + 3 + 2
An easier formula could be used by using multiplication.
This would be [7(0) + 5(3) + 7(5) + 3(6) + 2(8)] / 24
This is a lot easier to read!
Now to solve it.
7 • 0 = 0
5 • 3 = 15
7 • 5 = 35
3 • 6 = 18
2 • 8 = 16
0 + 15 + 35 + 18 + 16 = 84
84 / 24 = 3.5
The mean is 3.5, or $3.50
This means that the average weekly allowance amongst these students is $3.50.
Hope this helps!
2+4z-18
change it so it's an equation
2+4z-18=0
then get 4z alone on one side by subtracting 4z from both sides
2-18=-4z
-16= -4z
divide both sides by -4
a negative divided by a negative becomes positive
4 =z
plug it in
2+4(4)-18
4x4 is 16
2+16-18=0
0=0
the same can be done for the second one 2+k-8
make it 2+k-8=0
move the k to get it alone so subtract k from both sides
2-8=-1k
-6 = -1K
you can divide by K to make K=6
plug in 2+6-8=0
0=0
I would need to have the same book and go to page 73 to be able to answer it. By the way, do you have any friends that have the answer?
2/20 because if you do 1/10 + 1/10 = 2/20