Laplace transform initial value problem

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Homework Statement



Use the Laplace transform to solve the following initial value problem:
x' = 7 x + 5 y, y'= -2 x + e5t, x(0)=0, y(0)=0

Find the expressions you obtain by taking the Laplace transform of both differential equations and solving for Y(s) and X(s)

Homework Equations





The Attempt at a Solution


I'm confused on how to deal with the the x and y in each equation. We didn't do an example like this in class so I'm a little lost. We did it with one equation, but not two. Any help would be greatly appreciated!
 
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Then take the Laplace transform of both x and y! It's exactly the same. You will get two equations for the two Laplace transforms. Solve for each transform, then take the inverse transform to find x and y. It might be a good idea to let the variable be the usual "s" in one transform and, say, "t" in the other.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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