The coordinate of the body changes over time according to the law x = 30-5t. How long after the start

The coordinate of the body changes over time according to the law x = 30-5t. How long after the start of the movement will the coordinate of this body be 55 meters?

Given:

x (t) = 30 – 5 * t – the dependence of the coordinates of the body on time;

x = 55 meters is the required coordinate.

It is required to determine t (seconds) – after how long the body coordinate will be equal to x.

Substitute the required coordinate of the body into the equation of the coordinate versus time:

55 = 30 – 5 * t;

5 * t = 30 – 55;

5 * t = – 25;

t = -5 seconds.

Since time cannot have a negative value, this means that the coordinate of the body will never become equal to 55 meters. Indeed, the analysis of the body’s motion shows that it moves in the negative direction of the coordinate system.

Answer: the coordinate of the body will not be equal to 55 meters, since the body moves in the negative direction of the coordinate system.