Answer: x=3 and y=−2
Step-by-step explanation:
x=−2y−1;4x−4y=20
Step: Solve x=−2y−1 for x:
Step: Substitute−2y−1 for x in 4x−4y=20:
4x−4y=20
4(−2y−1)−4y=20
−12y−4=20(Simplify both sides of the equation)
−12y−4+4=20+4(Add 4 to both sides)
−12y=24
−12y
−12
=
24
−12
(Divide both sides by -12)
y=−2
Step: Substitute−2 for y x=−2y−1:
x=−2y−1
x=(−2)(−2)−1
x=3(Simplify both sides of the equation)
Answer:
A helping to register voters in your precinct
Step-by-step explanation:
To compare the two classes, the Coefficient of Variation (COV) can be used. The formula for COV is this:
C = s / x
where s is the standard deviation and x is the mean
For the first class:
C1 = 10.2 / 75.5
C1 = 0.1351 (13.51%)
For the second class:
C2 = 22.5 / 75.5
C2 = 0.2980 (29.80%)
The COV is a test of homogeneity. Looking at the values, the first class has more students having a grade closer to the average than the second class.
Answer:
option D and E just did it hope i help
Step-by-step explanation: