Whats the answer and work for this problem (3)

Mathematics

1 answer:

mamaluj [8]4 years ago

3 0

This is a system of equations. You can solve it by substitution or elimination. I'm going to use substitution x - 2y = -4.5; add 2y to each side x - 2y + 2y = -4.5 + 2y; simplify x = 2y - 4.5 2(2y - 4.5) + 3y = 12 4y - 9 + 3y = 12 7y - 9 = 12 7y - 9 + 9 = 12 + 9 7y = 21 y = 3 <--------first answer x - 2y = -4.5 x - 2(3) = -4.5 x - 6 = -4.5 x -6 + 6 = -4.5 + 6 x = 1.5 <--------second answer Check: 2(1.5) + 3(3) = 12? 3 + 9 = 12? 12 = 12; It checks 1.5 - 2(3) = -4.5? 1.5 - 6 = -4.5? -4.5 = -4.5; It checks x = 1.5 and y = 3 <-----------Final Answer

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Step-by-step explanation:

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Elena L [17]

Use the given values in the compound interest formula to solve for time, n.

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power rule of logarithmic moves exponent

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