Answer:
a) y - 2.5 = 1.25(x - 3)
b) i) Δx = 2.25
ii) Δy = 2.8125
c) y = 5.3125
Step-by-step explanation:
We are given the proportional relationship between the rates of change of x and y:
We are also given the point:
which written as a Cartesian coordinate is:
We can graph this relationship by determining the slope (m), then plugging that and the given point into the point-slope form equation.
Δy = 1.25 · Δx
↓ dividing both sides by Δx
Δy / Δx = 1.25
m = Δy/Δx = 1.25
↓ plugging into the point-slope form equation
y - 2.5 = 1.25(x - 3)
From x = 3 to x = 5.25, we can identify the change in x as:
Δx = 5.25 - 3
Δx = 2.25
Using the given proportional relationship, we can solve for the corresponding change in y:
Δy = 1.25 · Δx
Δy = 1.25 · 2.25
Δy = 2.8125
We can find the value of y at x = 5.25 by adding the Δy we just solved for to the given y-value at x = 3:
y = 2.5 + Δy
y = 2.5 + 2.8125
y = 5.3125