2 solutions. This is because the parabola will cross the x axis twice. We know this because -5 means the vertex will be 5 units below the x axis. and the parabola opens upwards because the first coefficient is positive. Hope this helped :)
Answer:
Class 7A collected 4.8 ounces of pure gold.
Step-by-step explanation:
<u>Key skills required are: Percentages, Multiplication</u>
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- We only need the information about Class 7A. They collected 40 oz that contains 12% gold.
- In other words, this means that 12% of that 40 oz gold sand is pure gold.
Here we have to do 12% x 40 to find the number of oz of pure gold. We first have to convert 12% into a decimal. Divide it by a 100 (or move the decimal point 2 places to the left) and you will get 0.12.
<em>Do 0.12 x 40 and you will get 4.8</em>
Therefore, there are 4.8 oz of pure gold in Class 7A's gold sand
I really don't know how toowrk it out on paper, I'm afraid. I just looked at it, and somehow knew that the answers are 7 and 9.