Choose the equation below that represents the line that passes through the point (−2, −1) and has a slope of 5.
y − 1 = 5(x − 2)
y + 1 = 5(x + 2)
y + 2 = 5(x + 1)
y − 2 = 5(x − 1)
and this one
Which of the following statements best describes the effect of replacing the graph of y = f(x) with the graph of y = f(x) + 20?
The graph of y = f(x) will shift left 20 units.
The graph of y = f(x) will shift down 20 units.
The graph of y = f(x) will shift up 20 units.
The graph of y = f(x) will shift right 20 units.
2 answers
On the first one, all you are doing is adding 20 to f(x), which just adds 20 to y. So, the graph shifts up 20.
Use the point-slope form of the line:
y - (-1) = 5(x - (-2))
or
y + 1 = 5(x+2)
Use the point-slope form of the line:
y - (-1) = 5(x - (-2))
or
y + 1 = 5(x+2)
2 answers