Question 486663
You can get rid of the "a"s in the denominator by multiplying all terms on both sides by a as follows:
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{{{(a*2a)/a + (a*1)/a = a*4}}}
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The a in the numerator cancels with the a in the denominator as follows:
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{{{(cross(a)*2a)/cross(a)+ (cross(a)*1)/cross(a) = 4a}}}
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and what's left is:
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{{{2a + 1 = 4a}}}
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Subtract 4a from both sides:
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{{{2a - 4a + 1 = 4a - 4a}}}
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and this simplifies to:
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{{{-2a + 1 = 0}}}
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Next subtract 1 from both sides:
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{{{-2a + 1 - 1 = -1}}}
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On the left side the +1 and -1 cancel each other out and this reduces the equation to:
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{{{-2a = -1}}}
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Solve for a by dividing both sides by -2:
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{{{(-2a)/(-2) = (-1)/(-2)}}}
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and the answer becomes:
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{{{a = 1/2}}}
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That's the answer to this problem.
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Hope this helps you to see your way through the problem.