Question

Evaluate each expression.

Answer 1

Answer:

Please check the explanation.

Step-by-step explanation:

Solving the expressions

7)

given the expression

$\left(-7\right)+\:\left(-10\right)\:-\:5\:+2$

• $\mathrm{Follow\:the\:PEMDAS\:order\:of\:operations}$

• $\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:\:$

• $\mathrm{Apply\:rule\:}+\left(-a\right)\:=\:-a$

so

$=\left(-7\right)-10-5+2$

$=-17-5+2$

$=-22+2$

$=-20$

8)

$\left(-9\right)+4+\left(-8\right)-\left(-7\right)$

• $\mathrm{Follow\:the\:PEMDAS\:order\:of\:operations}$

• $\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:\:$

• $\mathrm{Apply\:rule\:}+\left(-a\right)\:=\:-a$

so

$=-5+\left(-8\right)-\left(-7\right)$

$=-5-8-\left(-7\right)$

$=-13-\left(-7\right)$

$=-13+7$

$=-6$

9)

$\left(-6\right)\:-\:\left(2\:\times \:4\right)\:-\:\left(-1\right)\:$

• $\mathrm{Follow\:the\:PEMDAS\:order\:of\:operations}$

• $\mathrm{Add\:and\:subtract\:\left(left\:to\:right\right)}\:\:$

so

$\left(-6\right)-\left(2\times \:4\right)-\left(-1\right)$

Calculate within parentheses

$=\left(-6\right)-8-\left(-1\right)$

$=-14-\left(-1\right)$

$=-14+1$

$=-13$

10)

$\left(-8\right)\:+\:\left(-4\:\div \:-4\right)\:-\:8$

solving

$\left(-8\right)+\left(-\frac{4}{-4}\right)-8$

$\mathrm{Remove\:parentheses}:\quad \left(-a\right)=-a$

$=-8-\frac{4}{-4}-8$

$=-8-\left(-1\right)-8$

$\mathrm{Apply\:rule}\:-\left(-a\right)=a$

$=-8+1-8$

$\mathrm{Add/Subtract\:the\:numbers:}\:-8+1-8=-15$

$=-15$