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100 POINTS solve the system using linear combination. show all work.{ 5x + 3y = 41 {3x - 6y = 9

2 Answers

7 votes
5x+3y = 41 multiply whole thing by -2 so the y’s cancel out
3x-6y = 9

Becomes
-10-6y=-82
- subtract
3x-6y = 9

=
-13x+0y=-91
X=7

Plug in x to find y
3(7)-6y=9
21-6y=9
Y=2


User Morewry
by
4.4k points
6 votes

Answer:

y = 2

x = 7

Step-by-step explanation:

  • 5x + 3y = 41
  • 3x - 6y = 9

Make the coefficient of "y" in equation 1 same

{ 5x + 3y = 41 } * 2 → 10x + 6y = 82 ........equation 1

→ 3x - 6y = 9 ........equation 2

solving them using linear combination

  • 10x + 6y = 82
  • 3x - 6y = 9

============

  • 13x = 91
  • x = 7

Find y:

  • 5x + 3y = 41
  • 5(7) + 3y = 41
  • 3y = 41 - 35
  • 3y = 6
  • y = 2
User Freakwincy
by
4.2k points