Answer:
1.
2.
Step-by-step explanation:
1. Since this is a equation we know we have to get the variables to one side and the constants/rational numbers to the other. So you take 7y and you add -7y. You do that to the other side which will give you -4y=22. Since we cant have a negative variable, you flip the y to positive and flip the constant to negative leaving you 4y=-22. Then you distribute y leaving you y=-5.5
2.since we know the constants must be on 1 side of the equal sign, we subtract 123 on both sides, leaving us with 28y=-35. Distribute y and you get y=-0.8
1. -x+9y=-5
x-5y=1
-----------------
x=1+5y
-(1+5y)+9y=-5
-1-5y+9y=-5
-1+4y=-5
4y=-5-(-1)
4y=-5+1=-4
4y=-4
y=-4/4=-1
So x=1+5y=1+5(-1)=1-5=-4
Answer: x=-4, y=-1. (-4, -1).
2) -7x-y=13
8x+y=-14
------------------
y=-14-8x
-7x-(-14-8x)=13
-7x+14+8x=13
14+x=13
x=13-14=-1
y=-14-8(-1)=-14+8=-6.
Answer: x=-1, y=-6. (-1, -6).
3) x+7y=24
x-9y=-24
----------------
x=24-7y
24-7y-9y=-24
24-16y=-24
16y=24-(-24)=24+24=48
y=48/16=3
x=24-7(3)=24-21=3
Answer: x=3, y=3. (3, 3).
4). 3x+y=-21
x+y=-5
-------------------
x=-5-y
3(-5-y)+y=-21
-15-3y+y=-21
-15-2y=-21
2y=-15-(-21)=-15+21=6
y=6/2=3
x=-5-3=-8.
Answer: x=-8, y=3. (-8, 3).
5) 3x+6y=6
9x-12y=18
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Simplify 3x+6y=6 will get you x+2y=2,
x=2-2y,
9(2-2y)-12y=18
18-18y-12y=18
18-30y=18
30y=18-18=0
y=0/30=0
x=2-2(0)=2-0=2
Answer: x=2, y=0. (2, 0).
6) 6x+8y=26
-7x+2y=-19
-----------------
-4(-7x+2y)=-4(-19)
28x-8y=76
---------------------------
6x+8y=26
28x-8y=76
-----------------
34x=102
x=102/34=3
6(3)+8y=26
18+8y=26
8y=26-18=8
y=8/8=1
Answer: x=3, y=1. (3, 1)
BONUS:
-5x+5y=-25
3x+2y=10
---------------
Simplify -5x+5y=-25 you will get x-y=5
x=y+5
3(y+5)+2y=10
3y+15+2y=10
5y+15=10
5y=10-15=-5
y=-5/5=-1
x=-1+5=4
Answer: x=4, y=-1. (4, -1).
Answer:
because after decimal then value 0 dont have meaning
Answer:
C. The coefficient of variation is a measure of relative dispersion that expresses the standard deviation as a percentage of the mean, for any data on a ratio scale and an interval scale
Step-by-step explanation:
Th Coefficient of Variance is a measure of dispersion that can be calculated using the formula:
Where 
is the Standard Deviation
and 
is the sample mean
From the formula written above, it is shown that the Coefficient of Variation expresses the Standard Deviation as a percentage of the mean.
Coefficient of variation can be used to compare positive as well as negative data on the ratio and interval scale, it is not only used for positive data.
The Interquartile Range is not a measure of central tendency, it is a measure of dispersion.
Answer:
-100
-10, 10
Step-by-step explanation:
Let the smaller number be x.
Then the larger number is x + 20.
The product is x(x + 20).
Now you can write the function
y = x(x + 20)
y = x^2 + 20x
Take the first derivative of y with respect to x.
y' = 2x + 20
Set the first derivative equal to zero to find the x value for the minimum value of the function.
2x + 20 = 0
2x = -20
x = -10
The minimum value of the function occurs at x = -10. -10 is one of the two numbers.
y = x^2 + 20x
For x = -10,
y = (-10)^2 + 20(-10)
y = 100 - 200
y = -100
The minimum value of the product is -100.
x = -10
x + 20 = -10 + 20 = 10
The numbers are -10 and 10.
If you have not learned derivatives yet, then plot the function
y = x^2 + 20x
Now look at the graph and find the minimum y value and the x value at which it occurs.
The minimum y value is -100. That is the minimum product you are looking for.
The x value of the minimum function value is x = -10.
Then x + 20 = -10 + 20 = 10.
The numbers are -10 and 10.
