1. 


The graph of any equation in two variables is a straight line. 
2. 


The graph of any linear equation in two variables is a straight line. 
3. 


In a linear model of y as a function of x, the slope is measured in units of x per unit of y. 
4. 


In a linear model of y as a function of x, y changes by the same amount for every unit of change in x. 
5. 


To find the equation of a line, all you need is a point and the slope. 
6. 


The graph of a quadratic function f(x) = ax^{2}+bx+c (a 0) is never a straight line. 
7. 


A polynomial function is not a rational function. 
8. 


f(x) = 3x^{2}2x is not a quadratic function, since it lacks the constant term. 
9. 


If displacement is a linear function of time, then the slope of the graph represents the velocity. 
10. 


If the weekly sales q of an item priced at $p are given by q = 3p + 40, then the weekly sales decrease by 3 items for every $1 increase in price. 
11. 


A realvalued function of a real variable is a rule that assigns exactly one number to each specified input number in a specified domain. 
12. 


Some functions assign two or more numbers to each specified input number. 
13. 


If f(x) = x^{3}, then f(x+h) = x^{3} + h. 
14. 


If f(x) =  1
2x  , then f(x+h)  =  1
2x  + h. 

15. 


If f(x) =  x
x  1  , then the largest possible domain of f consists of all real numbers except 0. 

16. 


The regression line associated with two data points (with different xcoordinates) always passes through both points. 
17. 


The regression line associated with three data points (with different xcoordinates) always passes through at least two of those points. 
18. 


The regression line associated with a collection of more than two data points may pass through none of those points. 
19. 


The number 0.00346 is specified to 5 significant digits. 
20. 


When multiplying two numbers whose values are not known precisely, one should always round the answer to more significant digits than appear in the original factors. 