SOLUTION
Given the information in the image on the question tab;
We have to form triangles using points A and B, and points A and C;
Then find the slopes between A and B, and A and C;
Part A;
The slopes are equal.
Part B;
The initial value, or y-intercept, is the output value when the input of a linear function is zero. It is the y-value of the point at which the line crosses the y-axis.
The slope represents change in y over change in x. Therefore, in a distance vs. time graph, the slope is equal to distance/time, which represents the velocity.