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2 votes
Solve using substitution
y=3x-5
2x+5y=-42

User Rhapsody
by
7.6k points

1 Answer

5 votes

Answer:

Solution point is (-1,-9)

Explanation:

Put the value of y in the first equation into the second equation.

  • 2x + 5(3x - 5) = - 42 Remove the brackets on the left
  • 2x + 15x - 25 = - 42 Combine like terms on the left
  • 17x - 25 = - 42 Add 25 to both sides
  • 17x - 25 + 25 = - 42 + 25 Do the addition
  • 17x = - 17 Divide by 17
  • 17x/17 = -17/17 Do the division
  • x = - 1

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Solve for y

  • y = 3x - 6
  • x = -1
  • y = 3(-1) - 6
  • y = -3 - 6
  • y = - 9
User Jordie
by
8.4k points