Problem
If \( (a+b)^{2}=25, a b=6 \) then \( a^{2}+b^{2}=\cdots \)
Solution
Step 1 ：Step 1: Expand \((a+b)^{2}\) using the formula \((a+b)^{2}=a^{2}+2ab+b^{2}\)
Step 2 ：Step 2: Substitute given values: \(25=a^{2}+2(6)+b^{2}\)
Step 3 ：Step 3: Solve for \(a^{2}+b^{2}\): \(a^{2}+b^{2}=25-12=13\)
