Evaluate x^2 - (xy - y) for x satisfying 3(x + 3)/5 = 2x + 6 and y satisfying - 2y - 10 = 5y + 18.

To evaluate the expression, we first need to solve the linear equations for x and y. A linear equation is an equation of the first degree, meaning it can be written in the form ax + b = 0. We can isolate the variable by performing algebraic operations, such as addition, subtraction, multiplication, or division, to find the values of x and y that satisfy the equations.

Once we have the values of x and y, we can substitute these values into the expression x^2 - (xy - y). Substitution is a fundamental algebraic technique where we replace a variable with its corresponding value. This allows us to simplify the expression and compute the final result based on the values obtained from the linear equations.

Evaluating an expression involves calculating its value after substituting the variables with their respective numerical values. In this case, we will compute x^2 - (xy - y) using the values of x and y found earlier. Understanding how to correctly perform operations such as addition, subtraction, multiplication, and exponentiation is crucial for obtaining the correct final answer.