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 Question from Destiny, a student: I wanted to know the value of x-(3x+5) if x=-2

Hi Destiny,

Let me try a similar problem.

What is the value of $5x + (7 - 4x)$ if $x = -3?$

In evaluating this expression I need to perform the operations inside the parentheses first so I need to evaluate $7 - 4x$ when $x = -3.$

Substituting $x = -3$ into $7 - 4x$ gives me $7 - (4 \times (-3)) = 7 - (-12) = 7 + 12 = 19.$

Hence the expression becomes

$5x + (7 - 4x) = 5 \times (-3) + 19 = -15 + 19 = 4.$

Now try your problem and write back if you need more help.

Penny

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