How do you evaluate $5^2(-3)-46+7$ ?

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Answer 1 · 2016-09-16T12:20:50

$- 92$

We have: $5^(2) cdot (- 3) - 4 cdot 6 + 7$

Let's use the rules of operator precedence, "PEMDAS":

$= 25 cdot (- 3) - 4 cdot 6 + 7$

$= - 75 - 4 cdot 6 + 7$

$= - 75 - 24 + 7$

$= - 99 + 7$

$= - 92$

Answer 2 · 2016-09-16T14:53:34

$-92$

In any expression with different operations, it is important to COUNT terms first. Each term will simplify to a single answer.

Within each term the order of operations is applied:
Brackets
Powers and roots
multiply and divide

You can work in different terms in the same line.

Once there is a single answer to each term, these are added or subtracted in the last step, working from left to right.

$color(red)(5^2)xx(-3) color(blue)(-4xx6)color(lime)(+7)" "larr$ there are 3 terms

= $color(red)(25xx(-3) color(blue)(-24)color(lime)(+7)$

= $color(red)(-75) color(blue)(-24)color(lime)(+7)$

It is often easier to re-arrange the terms with the plus terms at the beginning and the minus terms at the end.

= $color(lime)(+7)color(red)(-75) color(blue)(-24)$

= $-92$

How do you evaluate 5^2*(-3)-4*6+75^2*(-3)-4*6+7?