Answer:
a. the Student's t-distribution with 124 degrees of freedom
Step-by-step explanation:
We have no information about the standard deviation of the population, just for the sample, which means that the student's t-distribution is used.
Degrees of freedom
Sample size subtracted by 1.
125 households were sampled.
125 - 1 = 124 degrees of freedom.
So the correct answer is:
a. the Student's t-distribution with 124 degrees of freedom
Step 1: Find the slope:

This gives you
, but we need to find b.
To find b, substitute in one (x,y) pair and it doesn't matter which one. I'll go with (4,-2):
![\begin{aligned}-2&=-\dfrac{3}{2}(4)+b\\[0.5em]-2&=-6+b\\[0.5em]4&=b\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D-2%26%3D-%5Cdfrac%7B3%7D%7B2%7D%284%29%2Bb%5C%5C%5B0.5em%5D-2%26%3D-6%2Bb%5C%5C%5B0.5em%5D4%26%3Db%5Cend%7Baligned%7D)
Now take that b-value and plug in into the slope-intercept form:

It's always a good idea to toss in the other x-value from the other point, to make sure it checks out.
Answer=
y=-3+3
y=0
the sum of -3+3 is zero.
Step-by-step explanation:
given
3x + y = 9
Writing In slope intercept form , y = mx + c
y = -3x + 9
comparing the given equation with y = mx + c
slope (m) = - 3
y-intercept (c) = 9
Hope it will help :)