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2 years ago

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

2 answers:

6 0

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

PIT_PIT [208]2 years ago

4 0

Answer:

y = 2

x = 7

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

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