Answer:
Yes, it is. Functions can only have one output (y) for each input (x). Furthermore, this means each x value will only have one y passing through it. Thus if we plot it on a graph and it passes through a horizontal line more than once, it is not a function. This is called the vertical line test. 
 
        
                    
             
        
        
        
Answer:
78% (to the nearest tenth)
Step-by-step explanation:
Volume of a cube = (length )³
Let the length of the cube = y
Original volume = y³
if the length is decreased by 40%, then new length = 1- (40% of y)
                                                                                      = 1-0.4y
                                                                                      =  0.6%
New volume (after decreasing the length) = (0.6y)³
                                                                       =  0.216y³
% Volume decrease = (Original volume - New volume)/Original Volume x 100%
                                  =  (y³ - 0.216y³)/ y³  x 100%
                                  = 0.784y³/y³  x 100%
                                  =78.4%
                                 ≈78%
 
        
                    
             
        
        
        
The regression equation for the data given is y= -8.57 -2.31x
Step-by-step explanation:
The first step is to form a table as shown below;
x           y          xy         x²         y²
1            4           4          1          16
2            1            2          4         1
3            5          15         9         25
4             10         40        16       100
5             16         80        25      256
6              19        114       36        361
7               15       105       49       225
28             60       360      140     984   ------sum
A linear regression equation is in the form of y=A+Bx
where ;
x=independent variable
y=dependent variable
n=sample size/number of data points
A and B are constants that describe the y-intercept and the slope of the line
Calculating the constants;
A=(∑y)(∑x²) - (∑x)(∑xy) / n(∑x²) - (∑x)²
A=(60)(140) - (28)(360)  / 7(140)-(28)²
A=8400 - 10080 /980-784
A= -1680/196
A= - 8.57
B= n(∑xy) - (∑x) (∑y) / n(∑x²) - (∑x)²
B= 7(360)-(28)(60) / 7(60) - (28)²
B=2520 - 1680 /420-784
B=840/-364
B= -2.31
y=A+Bx
y= -8.57 -2.31x
Learn More
Regression equation :brainly.com/question/12280902
Keywords : equations, regression line, data
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Answer:
I think that would be A sorry if I'm wrong