Answer:
y = -(5/2)x -2
Explanation:
The general formula for a straight line is y – mx + b.
The image below shows the graph of the line.
Step 1. <em>Calculate the slope</em>.
Slope = m = Δy/Δx = (y₂-y₁)/(x₂-x₁)
x₁ = 0; y₁ = -2
x₂ = -2; y₂ = 3 Calculate m
m = [3-(-2)]/(-2-0)
m = (3+2)/(-2)
m = 5/(-2)
m = -5/2
Step 2. <em>Calculate the y-intercept </em>
When x = 0, y = 2.
The y-intercept (b) is at y = -2
Step 3. <em>Write the equation </em>for the graph
y = mx + b
y = -(5/2)x - 2
Answer:
Step-by-step explanation:
We want to find the equation of the parabola with a focus of and directrix
.
Considering the directrix, the quadratic graph must open downwards.
The equation of this parabola is given by the formula,
, where
is the vertex of the parabola.
The axis of this parabola meets the directrix at .
Since the vertex is the midpoint of the focus and the point of intersection of the axis of the parabola and the directrix,
and
.
The equation of the parabola now becomes,
.
Also is the distance between the vertex and the directrix.
This implies that .
Since the parabola turns downwards,
.
Our equation now becomes,
.
.
We make y the subject to get,
.
This is the same as
.
