Answer: Line D
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Explanation:
Note in the previous line C that Noah multiplied both sides by 5. This is to clear out the fractions, since each have a denominator of 5.
In line D, Noah only multiplied those outer '5's by the first term in each parenthesis group. He didn't use the distributive property correctly.
The distributive property is a*(b+c) = a*b+a*c.
The 'a' is multiplied to everything inside, which are the terms b and c.
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Here are what the steps should look like from line D and onward. Take note of the 30 and 100. This is from 5*6 = 30 and 5*20 = 100.
- D) 7*14 - 30 = 12*14 - 100
- E) 98 - 30 = 168 - 100
- F) 68 = 68
We end up with the same thing on both sides. So this confirms that x = 14/5 is the solution to the original equation.
