Question
How do you reflect -0.25x + 5 across the x-axis?
Answers
Reiny
did you mean
y = -.25x + 5 ?
several ways to do this, here is a way that is simple to understand
Let's take two points on the line
x = 0, y = 5 ---> (0,5)
x = 4, y = 4 ---> (4,4)
when we reflect across the x-axis, the x values stays the same, but the way values becomes opposite
so (0,5) -----> (0,-5)
and (4,4) ----> (4,-4)
slope of new line = (-4+5)/(4-0) = 1/4
and since (0, -5) is the y-intercept
we have
y = (1/4)x - 5 or y = .25x - 5
sketch the above to see the situation.
y = -.25x + 5 ?
several ways to do this, here is a way that is simple to understand
Let's take two points on the line
x = 0, y = 5 ---> (0,5)
x = 4, y = 4 ---> (4,4)
when we reflect across the x-axis, the x values stays the same, but the way values becomes opposite
so (0,5) -----> (0,-5)
and (4,4) ----> (4,-4)
slope of new line = (-4+5)/(4-0) = 1/4
and since (0, -5) is the y-intercept
we have
y = (1/4)x - 5 or y = .25x - 5
sketch the above to see the situation.
Anonymous
If the function were h(x) = -0.25x + 5, could I multiply by -1 to get h(x) = 0.25 + 5? Or would this be -h(x) = 0.25 + 5?