The co-ordinates of the point of intersection of lines ax + by-9 andox

1.	The co-ordinates of the point of intersection of lines ax + by-9 andox + ay = 5 is (3,-1). Find the values of a and b.(i)
Answer» ax+by = 9 and bx+at =5 (3,-1) is the coordinates of the point of intersection of these two lines. x= 3 and y=-1 put the values of x and y in the equations given above. a(3)+b(-1)= 9 and b(3)+a(-1) =5 3a -b =9 and. 3b -a = 5......i) b= 3a-9 put the value of b in ..i) eq. 3(3a-9)-a = 5 9a - 27 -a = 5 8a -27= 5 8a = 32 a= 32/8 a= 4 put a=4 in i) eq. 3b -4 =5 3b= 9 b=9/3 b=3 how did you prove that 3 and -1 are the coordinates

The co-ordinates of the point of intersection of lines ax + by-9 andox + ay = 5 is (3,-1). Find the values of a and b.(i)

Answer»

ax+by = 9 and bx+at =5

(3,-1) is the coordinates of the point of intersection of these two lines.

x= 3 and y=-1

put the values of x and y in the equations given above.

a(3)+b(-1)= 9 and b(3)+a(-1) =5

3a -b =9 and. 3b -a = 5......i)

b= 3a-9

put the value of b in ..i) eq.

3(3a-9)-a = 5

9a - 27 -a = 5

8a -27= 5

8a = 32

a= 32/8

a= 4

put a=4 in i) eq.

3b -4 =5

3b= 9

b=9/3

b=3

how did you prove that 3 and -1 are the coordinates