We looking for distance

240 m

Step-by-step explanation:

Figure is attached.

The distance the particle travels is the area under the v-t graph over the time interval from 0 min to 4 min.  The reason you can't just multiply velocity by time is that the velocity is changing at a constant rate over the given time interval (the line is going upward--the particls is speeding up).

What's the area under the graph?

The red outline forms a trapezoid.  The area of a trapezoid is    where the b's are the lengths of the two parallel base and  h  is the height (the distance between the bases).

Reading the graph carefully (notice the scales!)...

ian gone lie this got me confused

step-by-step explanation:

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.