Answer:
$54
Step-by-step explanation:
First, we calculate the amount she paid for each pen.
$255/5 = $51
She paid $51 for each pen.
She made a profit of $3 per pen, so she sold each pen for $51 + $3 = $54
Answer: $54
Answer:

Step-by-step explanation:
The domain of the function is the set of all possible inputs for the function. Therefore, the set of all possible inputs is
.
Answer:
3n^2+9+5n^4+55n
Step-by-step explanation:
Steps
$\left(3n^2+9+5n^4-3n\right)+\left(-9n\left(-7\right)-5n\right)$
$\mathrm{Remove\:parentheses}:\quad\left(a\right)=a,\:-\left(-a\right)=a$
$=3n^2+9+5n^4-3n+9n\cdot\:7-5n$
$\mathrm{Add\:similar\:elements:}\:-3n-5n=-8n$
$=3n^2+9+5n^4-8n+9\cdot\:7n$
$\mathrm{Multiply\:the\:numbers:}\:9\cdot\:7=63$
$=3n^2+9+5n^4-8n+63n$
$\mathrm{Add\:similar\:elements:}\:-8n+63n=55n$
$=3n^2+9+5n^4+55n$
<span>1 1/4 - 5/8
= 5/4 - 5/8
= 10/8 - 5/8
= 5/8
</span><span>difference between 1 1/4 and 5/8 is 5/8
</span>
hope it helps