If x=2, y= -5, and z= -1, then what does (x-y) (x+y-z) equal?

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Answer 1 · 2018-04-19T07:12:45

$(x - y) (x + y - z) = (2 + 5) \times (2 - 5 + 1) = 7 \times (- 2) = - 14$ $(x-y)(x+y-z) = (2+5)xx(2-5+1) = 7xx (-2) = -14$

First, substitute the values of $x$ $x$ , $y$ $y$ , and $z$ $z$ .

$(x - y) (x + y - z) = [2 - (- 5)] [2 + (- 5) - (- 1)]$ $(x-y)(x+y-z) = [2- (-5)][2+ (-5) - (-1)]$

Next, we remove unnecessary addition and subtraction signs to complete the expression.

$- and + = -$ $- and + = -$

$- and - = +$ $- and - = +$

$+ and + = +$ $+ and + = +$

So

$(2 + 5) (2 - 5 + 1)$ $(2+5)(2-5+1)$

Next, we complete the expressions inside the brackets (order of operations).

$(7) \times (- 2)$ $(7)xx(-2)$

Finally, to complete the expression, we carry out the multiplication:

$- 14$ $-14$