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# If ab = 10, and a^{2} + b^{2} = 30, solve for y in the equation, y = (a + b)^{2}.

Question:

A
50

Explaination

y = (a + b)^{2}. Expanding the equation results in y = a^{2} + b^{2} + 2ab. You know that a^{2} + b^{2} = 30, and ab = 10. When you substitute these known values into the equation, you get y = 30 + 2(10). Solving for y, results in y = 50.