Question

Part A: Solve −np − 70 < 40 for n. Show your work. (4 points) Part B: Solve 4w − 7k = 28 for k. Show your work.

Answer 1

Hey!

For part A, let's write the problem,
$-np-70\ \textless \ 40$
Add $70$ to both sides...
$-np-70+70\ \textless \ 40+70$
$-np\ \textless \ 110$
We are going to reverse the inequality, to do this we are going to multiply both sides by $-1$.
$\left(-np\right)\left(-1\right)\ \textgreater \ 110\left(-1\right)$
$pn\ \textgreater \ -110$
Divide both sides by $p$.
$\frac{pn}{p}\ \textgreater \ \frac{-110}{p}$
Our answer would be,
$n\ \textgreater \ -\frac{110}{p}$

Let's go with Part B. Let's write the problem,
$4w-7k=28$
Subtract $4w$ from both sides,
$4w-7k-4w=28-4w$
$-7k=28-4w$
Divide both sides by $-7$.
$\frac{-7k}{-7}=\frac{28}{-7}-\frac{4w}{-7}$
If we simplified it, we would be left with,
$k=-\frac{28-4w}{7}$

Thanks!
-TetraFish