Calculate the value of coordinate of Point B in which point A is $7$ units from zero on a number line. Point B is $3$ units to the left of the opposite of Point A.

In this type of question, use the concept of number line that from the origin if the number goes to right it is positive and when it goes from left of origin it is negative..

Since, It is given that the point A is units from zero on a number line and Point B is units to the left of the Point A.

So, if it is shown in number line to clearify that:

On the number line, the coordinate of the point on the right side of the origin is positive and on the left side of the origin it is negative.

Since, the coordinate of point B is positive so, point A must also lie on the right side of the origin.

Now, point A and B, start from zero and move$7$ units to the and for point B move $3$ unit to the left of the point A.

So, the point B be $7unit-3unit=4unit$.