Answer: $28.30✔️
Step-by-step explanation:
Let C = cost before tax
Cell phone costs = C + C·6% = $30
C(1 + 0.06) = $30
C = $30/1.06 = $28.30
Answer: $28.30✔️
<h3> Verify </h3>
Cell phone after tax = $28.30 + $28.30·6/100 = $28.30 + $1.70 = $30✔️
<h2><em>Spymore </em></h2>
Answer:

Step-by-step explanation:
All of the sides are the same length.



Answer:
1) -17x-9
Step-by-step explanation:
1)
(-2x^3+x-5)+(x^3-3x-4)
Combine like terms using P.E.M.D.A.S:
(-2x^3+x-5)+(x^3-3x-4)
(-9x-5)+(-8x-4)
Combine like terms:
(-2x^3+x-5)+(x^3-3x-4)
(-9x-5)+(-8x-4)
-17x-9
I hope this helps a bit!☺
Make variables for each
L = library books
P = telephone books
T = text books
so.... L+P = 2T
now we have to fill in numbers