From the eqn \(x^2 = 49\)
therefore, \(x = 7, -7\)

when \(x\) is replaced by either \(7\) or \(-7\) the two quantities are equal
When \(x = 7\) both quantities are \(0\)
when \(x = -7\) both quantities are \(98\)
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x can be eithr +7 or -7. In options A and B, the term including x are both -7x, and the other term has same value.

x^2 or 49, both are same.

Hence both A and B are equal.

Explanation

Remember that when a variable is squared, it yields a positive and a negative solution; hence, \(x^2 - 49 = 0\) means that \(x^2 = 49\) and x = ± 7.

If x = 7, then both quantities are equal to zero. If x = –7, then both quantities are equal to 98. The answer is choice (C).
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We get x^2 = 49 from the given condition.

Qty A is x^2 - 7x which is nothing but 49 -7x
Qty B is -7x + 49 which I can write as 49 -7x

Observe both the quantities now!

What do you see??

Both are same!!!
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My Answer is C

x^2=49 -> x=7 or x=-7. In either case, QA=QB -> C.
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