Description for Correct answer:
\( \Large 3x + 7 = x^{2} + M = 7x + 5 \)

We can write

7x + 5 = 3x + 7

=> 4x = 2

=> x = \( \Large \frac{1}{2} \)

Now, \( \Large 3x + 7 = x^{2} + M \)

or, \( \Large M = 3x + 7 - x^{2} \)

= \( \Large 3 \times \frac{1}{2} + 7 - (\frac{1}{2})^{2} \)

= \( \Large 1 \frac{1}{2} + 7 - \frac{1}{4} = 1 \frac{1}{4} + 7 = 8 \frac{1}{4} \)