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32 votes
Solve this system of linear equations. Separate

the x- and y-values with a comma.
15x = -42 - 19y
3x = -54 - 19y

User Alex Dn
by
3.1k points

2 Answers

21 votes
21 votes

15x=-42-19y

  • 15x+19y+42=0-(1)

3x=-54-19y

  • 3x+19y+54=0--(2)

Subtract both

  • 12x-12=0
  • 12x=12
  • x=1

Put in second

  • 3(1)+19y+54=0
  • 19y+57=0
  • y=-3

So

  • (x,y)=(1,-3)
User Pedro Madrid
by
2.6k points
21 votes
21 votes

Answer:

1, -3

Explanation:

Question

Solve the system of linear equations:

  • 15x = -42 - 19y
  • 3x = -54 - 19y

-------------------------------------------------------------------------------------

Solution

Subtract the equations to eliminate y:

15x = -42 - 19y

- 3x = -54 - 19y

----------------------

12x = 12

⇒ x = 12 ÷ 12

⇒ x = 1

Now substitute the found value of x into one of the equations and solve for y:

⇒ 15x = -42 - 19y

⇒ 15(1) = -42 - 19y

⇒ 15 = -42 - 19y

⇒ 19y = -42 - 15

⇒ 19y = -57

⇒ y = -57 ÷ 19

⇒ y = -3

Therefore, x = 1 and y = -3

User Boris Silantev
by
3.0k points