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Solve the system by substitution: 4x - 9y = -23, y = 3x

User Misol Goh
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Final answer:

To solve the given system of equations by substitution, substitute y = 3x into the first equation and solve for x, then plug that x value back into the second equation to find y. The solution is x = 1 and y = 3.

Step-by-step explanation:

The question involves solving a system of equations by substitution. We have two equations:

  • 4x - 9y = -23
  • y = 3x

First, we'll substitute the second equation into the first to solve for x:

  1. Substitute y = 3x into 4x - 9y = -23:
  2. 4x - 9(3x) = -23
  3. 4x - 27x = -23
  4. -23x = -23
  5. x = 1

Next, plug x back into the second equation to find y:

  1. y = 3(1)
  2. y = 3

The solution to the system of equations is x = 1 and y = 3, which represents the point where the lines would intersect on a graph.

User Vitaly  Muminov
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