Worksheet Worksheet 4
1.
Determine the value of \(x^2 + 2y^2\) when \(x = -1\) and \(y = 2\text{,}\) and when \(x = -2\) and \(y = -1\text{.}\) Write your results as if-then statements.
2.
Solve \(ax + by = c\) for using a complete presentation.
3.
Solve the equation \(3x - 2y - 4z = 24\) for the variable using a complete presentation.