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CCSS Persevere with Problems Suppose A and B represent linear expressions.

If A + B = 2x - 2 and A - B = 4x - 8, find A and B.

A = 3x - 5 and B = 3 - x

Step-by-step explanation:

The given linear expressions are:

A + B = 2x - 2 ... (1)

and A - B = 4x - 8 ... (2)

To find, the value of A and B = ?

Adding equations (1) and (2), we get

A + B + A - B = 2x - 2 + 4x - 8

⇒ A + A = 6x - 10

⇒ 2A = 2 (3x - 5)

⇒ A = 3x - 5

Putting the value of A in equation (1), we get

3x - 5 + B = 2x - 2

⇒ B = 2x - 2 - 3x + 5

⇒ B = 3 - x

Thus, A = 3x - 5 and B = 3 - x