We have to graph the position versus time.
We start by identifying the segments.
1) The initial position (x=0, y=0) is his house.
2) He drove for 4 minutes at a speed of 1 block/min. This means that we have a line with slope m=1 from x=0 to x=4. The value of y when x=4 is also 4.
Then, the final point of this segment is (4,4).
3) He spent 3 minutes in the store. This means that y=4 between x=4 and x=4+3=7.
The final point of this segment is (7,4).
4) He drove at a speed of 2 blocks/minute (slope m=2) for 6 blocks until he got to the bank. Then, the new position is y=7+6=13. If the slope is m=2, then he will spent 6/2=3 minutes to reach the bank. As he already spent 7 minutes, he arrived to the bank at x=7+3=10.
Then, the final position of this segment will be (10,13).
5) Then, he returns at a speed of 5 blocks every 4 minutes. This correspond to a slope m=-5/4. This slope is negative as he is now returning to his house and, then, y is decreasing.