Answer:
See explanation
Step-by-step explanation:
Solution:-
- The researcher claims :
" the average annual salary of part-time community college instructors is at least $45,000 "
- We will extract the claim made by the researcher to be the Null hypothesis:
Null Hypothesis : μ ≥ $45,000
- Any statement otherwise, or point of rejection criteria will denote the Alternate hypothesis that disbands the claim that:
" the average annual salary of part-time community college instructors is less than $45,000 " :
Alternate Hypothesis : μ < $45,000
- This type of test with a sample size of n = 25 < 30 and population standard deviation is also not given hints the use t-test statistics and t-critical value reject the claim.
Lower tail - one sample - T-test.
3x + y = 3
7x + 2y = 1
First isolate one of the variables (x or y) in one of the equations.
Isolate "y" in the first equation(because it is the easiest to isolate) and substitute it into the second equation.
3x + y = 3 Subtract 3x on both sides
3x - 3x + y = 3 - 3x
y = 3 - 3x
7x + 2y = 1
7x + 2(3 - 3x) = 1 [since y = 3 - 3x, you can substitute (3-3x) for "y"]
Multiply/distribute 2 into (3 - 3x)
7x + (3(2) - 3x(2)) = 1
7x + 6 - 6x = 1
x + 6 = 1 Subtract 6 on both sides
x = -5
Now that you know "x", substitute it into one of the equations (I will do both)
3x + y = 3
3(-5) + y = 3 [since x = -5, you can plug in -5 for "x"]
-15 + y = 3 Add 15 on both sides
y = 18
7x + 2y = 1
7(-5) + 2y = 1
-35 + 2y = 1 Add 35 on both sides
2y = 36 Divide 2 on both sides
y = 18
x = -5, y = 18 or (-5, 18)
Answer:
C
Step-by-step explanation:
Since these lines have the same slope and different y-intercepts, they are parallel lines. As such lines do not intersect, we can say that :
The system has no solutions.
Answer:
The third one
Step-by-step explanation: