Answer:
17
Step-by-step explanation:
Answer:
The provided study is an experiment.
Step-by-step explanation:
Consider the provided information.
Observational study: In this study observer only observe the subjects, and measure variables of interest without allocating treatments to subjects.
For example: you want to examine the side effect of smoke on lung.
Experiment study:The researchers are applying treatments to experimental units in the research, then the effect of the treatments on the experimental units is observed.
For example: Flipping a coin
Now consider the provided information:
Thirty university students are divided into two groups. One group receives free tutoring in mathematics comma the other doesn't. After one semester comma scores on final mathematical examinations are compared.
Here, the researcher applying treatment to experimental units.
Thus, the provided study is an experiment.
Answer:
115.08
Step-by-step explanation:
two points are (0,0) and (100, -800)
m = (y2-y1)/(x2-x1) = (-800-0)/(100-0) = -8
point slope form of the line is
y-y1 = m(x-x1)
y-0 = -8 (x-0)
y=-8x
this is in slope intercept form now
y=-8x
The solution (x,y) needs to work in both equations. With multiple choice you can do guess and test method. Otherwise you need to combine the two equations into one by substitution or elimination methods.
21. substitution works well here since one equation is y= x+3. you can easily substitute the (x+3) for y in the other equation.
2x + (x+3) = -6
3x + 3 = -6
3x = -9
x = -3
use this in either equation to find y.
y = (-3)+3
solution: (-3,0)
22. these both equal y so they equal each other.
4x - 1 = 3x +6
4x - 3x = 6 + 1
x = 7
use this in either equation to find y
y = 4(7) - 1
y = 28 - 1
y = 27
solution: (7,27)
23. one equation is y = 2x - 3. So substitute (2x -3) for y in the other equation.
4x = 2(2x - 3) + 6
4x = 4x - 6 + 6
4x = 4x
x = x
any solution will work, infinitely many.
24. infinitely many solutions means the two equations are the same equation. Like the previous one they didn't look the same but if you put them both in terms of y...
y= 2x-3
4x = 2y + 6
4x - 6 = 2y
(4x - 6)/2 = y
2x - 3 = y
same equation.
from the image, I can't see all options but A & C do not look like the same equations. It's got to be either B or D.