Question

If 3,1 is the point of intersection of lines ax+by =7 and bx+ay=5 find the values of a and b omtex classes

Answer 1

Answer:

Step-by-step explanation:

May be these one is right

Answer 2

Answer:

a = 2 and b = 1

Step-by-step explanation:

Given equations are :

ax + by = 7..........(1)

bx + ay = 5 .........(2)

As (3,1) is the point of intersection of given equations.

so, (3,1) will satisfy both of given equations.

Put (3,1) in equation (1),

$3a + b = 7$ ........(3)

Put (3,1) in equation (2),

$3b + a = 5$......... (4)

Now, solving above two equation we find the value of a and b.

Multiplying 3 with equation (3) and then subtracting equation (4),

$3(3a + b) - (3b + a) = 3 \times 7 - 5$

$9a + 3b - 3b - a = 21 - 5$

$8a = 16$ => $a = 2$

Put a=2 in equation (3)

b = 7 - 3a = 7 - 6 = 1

Hence, a = 2 and b = 1