If P = -(x - 2), Q = -2(y +1) and R = -x + 2y, find a, when P + Q + R = ax

Solution:

Given, P = -(x - 2), Q = -2(y +1) and R = -x + 2y

Also, P + Q + R = ax

We have to find the value of a 

P = -(x - 2) = -x + 2

Q = -2(y + 1) = -2y - 2

R = -x + 2y

Considering P + Q + R = ax

P + Q + R = -x + 2 + (-2y - 2) + (-x + 2y)

= -x + 2 - 2y - 2 - x + 2y

By combining like terms,

= -x - x + 2 - 2 - 2y + 2y

By distributive property,

= (-1 - 1)x + (2 - 2) + (-2 + 2)y

= (-2)x + 0 + (0)y

= -2x

Now, -2x = ax

a = -2

Therefore, the value of a is -2.

✦ Try This: If A = -(2x - 3), B = -3(y +2) and C = -4x + 3y + 3, find a, when A + B + C = 2ax

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 12

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NCERT Exemplar Class 7 Maths Chapter 10 Problem 69

If P = -(x - 2), Q = -2(y +1) and R = -x + 2y, find a, when P + Q + R = ax

Summary:

If P = -(x - 2), Q = -2(y +1) and R = -x + 2y, when P + Q + R = ax, the value of a is -2

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