Answer:
x = 2 or
x = -7
Step-by-step explanation:
(x - 2)(x + 7) = 0
x - 2 = 0
Add 2 to both sides
x - 2 + 2 = 2 + 0
x = 2
OR
x + 7 = 0
Subtract 7 from both sides
x + 7 - 7 = 0-7
x = -7
Therefore
x = 2 or
x = -7
Answer:
Explanation:
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<u>1. First find the density of your chain</u>
- Volume = displaced water volume
= Volume of Final level of water - initial level of water
= 20 ml - 15 ml = 5 ml
- Density = 66.7g / 5 ml = 13.34 g/ml
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<u>2. Second, write the denisty of the chain as the weighted average of the densities of the other metals:</u>
Mass of gold × density of gold + mass of other metals × density of other metals, all divided by the mass of the chain.
Calling x the amount of gold, then the amount of other metals is 66.7 - x:



Then, there are 26.47 grams of gold in 66.7 grams of chain, which yields a percentage of:
- (26.47 / 66.7) × 100 = 39.7%
Rational. There’s nothing further that you can do with this problem