 Hello and welcome to the session. I am Asha and I am going to help you with the following question which says, in question 4, point C is called the midpoint of line segment AB proves that every line segment has one and only one midpoint. Let us now begin with the solution and in question 4, if we are given a line segment AB a point C lies on AB such that we have AC is equal to CB. And this implies AC is equal to half of AB that is C is the midpoint of AC is equal to CB. And here in this question we have to show that every line segment one and only one midpoint line segment AB has two midpoints. Then D be a point which is a midpoint of AB. And to show that every line segment has one and only one midpoint we will show that this sides with C. We have suppose D is also the midpoint of line segment AB therefore in question 4 we have AD is equal to half of AB and also we have AC is equal to half of AB let this be equation number 1 and let this be equation number 2. So on comparing equation 1 and 2 we find that right inside of both the equations are equal so left inside are also equal and AC is equal to AD implies C coincides to D which further implies every line segment only one midpoint. This completes the solution take care and have a good day.