It is $300 that is the original price of the phone.
Answer:
Parabolas always have a lowest point (or a highest point, if the parabola is upside-down). This point, where the parabola changes direction, is called the "vertex". If the quadratic is written in the form y = a(x – h)2 + k, then the vertex is the point (h, k). This makes sense, if you think about it.
Step-by-step explanation:
56 - x = 728 + 2x
-x - 2x = 728 - 56
-3x = 672
x = 672/-3
x = -224
Hope that helps. If you have any doubts plz let me know.
You will divide 900 by 5000, (900\5000) your answer is .18 which is equal to 18%