Answer:
a^2 + 4bc
Step-by-step explanation:
Step 1: Expand the equations individually:
[tex]( a - b - c )^2 = a^{2} + b^{2} + c^{2} - 2ab + 2bc - 2ca \\(b-c)^2 = b^2 + c^2 - 2bc[/tex]
Step 2: Put them back together
[tex]= a^{2} + b^{2} + c^{2} - 2ab + 2bc - 2ca - (b^2 + c^2 - 2bc) + 2ab - 2ac\\= a^{2} + b^{2} + c^{2} - 2ab + 2bc - 2ca - b^2 - c^2 + 2bc + 2ab - 2ac\\\\[/tex]
Step 3: Final Answer
[tex]= a^{2} + 4bc[/tex]
