SOLUTION: Solve and check. 3a/7 = -2/5

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Question 54332: Solve and check.
3a/7 = -2/5
Answer by rchill(405) About Me  (Show Source):
You can put this solution on YOUR website!
Because both sides of the equation are fractions, you can either cross-multiply or multiply both sides by a common denominator. Using the latter, multiplying both sides by 35 gives us 5%2A3a=-2%2A7, which reduces to 15a=-14. Dividing both sides by 15 yields a=expr%28-14%2F15%29.
To check that, substitute it into the original equation: %283%2A%28expr%28-14%2F15%29%29%29%2F7=expr%28-2%2F5%29, which simplifies to -42%2F15%2F7=expr%28-2%2F5%29. That further simplifies to expr%28-42%2F15%29%2Aexpr%281%2F7%29=expr%28-2%2F5%29 and expr%28-6%2F15%29=expr%28-2%2F5%29, which finally reduces to expr%28-2%2F5%29=expr%28-2%2F5%29. Because that is a true statement, we know our answer is correct!