Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. His sister states that the expression should be x + x + 0.5x + y + y – 2. Who is correct? Explain.

The equations of both the sister are the same.Expression In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations that are formed according to rules which are dependent on the context.  Given to usGabriel Equation: [tex]2.5x+2y-2[/tex],Gabriel's Sister Equation: [tex]x+x+0.5x+y+y-2[/tex],Gabriel's Sister EquationOn further solving the equation we get,[tex]x+x+0.5x+y+y-2\\=2.5x + 2y-2[/tex]As we can see the equation transformed to Gabriel's Equation of total cost.Therefore, both the sisters are correct as the equations of both the sister are the same.Learn more about Expression: