solve for "y" so it is in the form y = mx + b. "m" is the slope and "b" is the y-intercept.
ax + by = c
by = -ax + c <em>subtracted "ax" from both sides</em>
y = (-a/b)x + c/b <em>divided both sides by "b"</em>
Answer: slope is -a/b and y-intercept is c/b
7.71 feet is your answer.
The sum of two numbers:
x + y = 108
The difference of the same two numbers:
x - y = 78
We can use substitution to figure out x and y:
x - y = 78 can be changed to x = 78 + y
We can plug this into the first equation:
78 + y + y = 108
78 + 2y = 108
2y = 30
y = 15
Now solve for x using any of the two equations. I'll use the first equation since it's easier:
x + 15 = 108
x = 93
B is the only number that is divisible by 3
Answer:
For the first city, the 95% confidence interval would be:
28,900 +/- 2300 x 3 = 28,900 +/-6900$
For the second city, the 95% confidence interval would be:
30,300 +/- 2100 x 3 = 30,300 +/- 6300$