STRAIGHT LINES

Dear Student

Say the x,y co ordinates of B are (x_b,y_b)

 

Since x+y =5 is bisector of AB    ,  B(x_b,y_b) is reflection of  A(1,2 )  Over x+y=5.

To Get  X_b  

Substitute the X co-ordinate of A i.e. 1 in to x+y=5 resulting y is equal to X_b

1+Y=5    ==>       Y= 4  ==>    X_b=4

Similarly to Get  X_b  

Substitute the y co-ordinate of A i.e. 2 in to x+y=5 resulting x is equal to y_b

X+2=5 ==>   X= 3  ==>  Y_b= 3

B(4,3)

Regards

Team

Topperlearning