Question

question 18
(a) write an equation to represent the relationship between d and t.
d = 1

Explanation:

Step1: Identify the relationship type

The graph is a straight line through the origin, so it's a proportional relationship, meaning \( D = kT \), where \( k \) is the constant of proportionality (speed here).

Step2: Calculate the constant \( k \)

From the graph, when \( T = 1 \) hour, \( D = 100 \) kilometers. So \( k=\frac{D}{T}=\frac{100}{1}=100 \).

Step3: Write the equation

Substitute \( k = 100 \) into \( D = kT \), we get \( D = 100T \).

Answer:

\( D = 100T \)