Equations of two lines of regression are 4x+3y+7 = 0 and 3x+ 4y + 8 = 0, themean of x and y are(a) 5/7 and 6/7(b) – 4/7 and –11/7(c) 2 and 4(d) None of these

The equations of two lines of regression are given as 4x + 3y + 7 = 0 and 3x + 4y + 8 = 0.

The mean of x and y can be found by solving these two equations simultaneously.

Step 1: Rewrite the equations in the form y = mx + c

For the first equation: 3y = -4x - 7, so y = -4/3x - 7/3

For the second equation: 4y = -3x - 8, so y = -3/4x - 2

Step 2: Solve the equations simultaneously

Set the two equations equal to each other and solve for x:

-4/3x - 7/3 = -3/4x - 2

Cross multiply to get rid of the fractions:

-16x - 28 = -9x - 6

Combine like terms:

7x = 22

So, x = 22/7 = 3.14

Substitute x = 3.14 into the first equation to solve for y:

y = -4/3(3.14) - 7/3 = -4.18 - 2.33 = -6.51

So, the mean of x is 3.14 and the mean of y is -6.51.

Therefore, the answer is not listed in the options given. So, the correct answer is (d) None of these.