1. Simplify the algebraic expression 3x2 - 2y + 7x2 - 5y + 3 and evaluate it for x = 2, y = 14. Identify the variables, constants, and coefficients in the simplified expression.
2. In a certain triangle, the second side is one-third of the first side in length. The third side is 2 meters less than the first side. The perimeter of the triangle is 26 meters. Form an algebraic equation to express the problem, and identify the variables, coefficients, and constants of the algebraic expression.
3. List anys four situations where variables can be used to replace number; convert each situation into an algebraic expression.