Thanks! If you answer these correctly I will love you forever. 1. If the slope of a straight line is -5 and if X (the variable on the horizontal axis) increases by 10, then Y (the variable on the vertical axis) will: a) decrease by .5 b) increase by .5 c) decrease by 50 d) increase by 50 e)... Show More
Most Helpful Guy
Because, a slope of "-5" means y = -5x (plus a constant, but that is irrelevant right now).
Insert "10" to the position of x. What do you get?
y = -5(10)
y = -50
Decreases by 50.
2-) c (this time you insert the variable to y, but everything else is same)
3-) d (same tactic)
Basically, y increases by 4850 - 1730 = 3120 when x increases by 500 - 100 = 400.
If y increases by 3080 and x increases by 400, then the slope of the line is 3120 / 400 = 7.8
Meaning that the equation should look like this:
Y = 7.8C + k (k is your y-intercept - the point where the line intersects with the vertical axis - and that is not given in the question so I can't tell you what k is, but we might not need it at all.)
None of the answers have the "7.8C" expression, so the correct answer must be "e - none of the above".