Question

Gabriel used the expression 2. 5x 2y – 2 to represent his total cost, and 28 – 2. 5x – 2y to represent the amount of change he should receive from $30. What was Gabriel’s error?

Answer 1

The error made by the Gabriel in calculating the change amount, is that he subtract the $2 instead of adding $2.

What is algebraic expression?

Algebraic expression are the expression which consist the variables, coefficients of variables and constants.

The algebraic expression are used represent the general problem in the mathematical way to solve them.

The expression used by the Gabriel to represent his total cost  is,

$2.5x+2y - 2$

As, Gabriel has to receive the change amount of $30. Thus, he has to subtract this amount from the total cost. This statement can be present as,

$\rm Change=30-(2.5x+2y - 2)\\\rm Change=30-2.5x-2y + 2\\\rm Change=32-2.5x-2y$

Now, the expression used by him to represent the amount of change he should receive from $30 is,

$28 -2.5x - 2y$

Hence, the error made by the Gabriel in calculating the change amount, is that he subtract the $2 instead of adding $2.

Learn more about the algebraic expression here;

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