To solve the problem (assuming it's the common type: Given (a + b = 5) and (ab = 3), find (a^2 + b^2)), follow these steps:

Step 1: Use the algebraic identity

The key identity here is:
[ (a + b)^2 = a^2 + 2ab + b^2 ]

Rearranging this identity to solve for (a^2 + b^2):
[ a^2 + b^2 = (a + b)^2 - 2ab ]

Step 2: Substitute the given values

We know (a + b = 5) and (ab = 3). Plug these into the formula:
[ a^2 + b^2 = (5)^2 - 2(3) = 25 - 6 = 19 ]

Answer: (\boxed{19})

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