At 2 seconds, what is the distance from the reference point?

Take note that in speed-time graph, the area under the curve represents the distance traveled.
So to determine the distance traveled at t=2, consider the bounded region from t=0 to t=2. (See attached.) 
Notice that the bounded region forms a triangle. So to get the area under the blue line from t=0 to t=2, apply the formula of area of triangle.
A = 1/2bh
The base of the triangle is 2 units and its height is 3 units. Plugging in the values yield:
A=1/2*2*3
A=3
So the area of the triangle is 3 units squared and this is equal to the distance traveled.
d i s t a n c e = A r e a=3
Therefore, at t=2seconds, the distance from the reference point is 3 meters.
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