Hello : here is a solution
Substitution doesn't work for this, but elimination does.
-6x-8y=-20 +6( x+6y=-6)
-6x-8y=-20 + 6x+36y=-36
-6x and 6x cancel each other, add -8 and 36 to get 28, and -20 and -36 to get -56.
28y=-56
divide by 28 on both sides.
Y= -2
Then substitute y into one of the equations.
x+6(-2)=-6
x-12=-6
x=6
The ordered pair is (6,-2).
The slope would have to be -3
Answer:
At 5% significance level, it is statistically evident that there is nodifference in the proportion of college students who consider themselves overweight between the two poll
Step-by-step explanation:
Given that a poll was taken this year asking college students if they considered themselves overweight. A similar poll was taken 5 years ago.
Let five years ago be group I X and as of now be group II Y

(Two tailed test at 5% level of significance)
Group I Group II combined p
n 270 300 570
favor 120 140 260
p 0.4444 0.4667 0.4561
Std error for differene = 
p difference = -0.0223
Z statistic = p diff/std error = -1.066
p value =0.2864
Since p value >0.05, we accept null hypothesis.
At 5% significance level, it is statistically evident that there is nodifference in the proportion of college students who consider themselves overweight between the two poll