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5 votes
Solve systems of equations for x + y, please!!

6x + 2y = 30
9x - 4y = 3

User Lysanne
by
5.1k points

2 Answers

7 votes
Answer is x+y=3+6=9

Thank me later lol
User Sedat Polat
by
5.6k points
2 votes

Answer:

9

Explanation:

6x + 2y = 30

9x - 4y = 3

if we double the first equation and add up to second one, we cancel 4y:

  • 12x+9x=60+3 ⇒ 21x=63 ⇒ x=3

now we can find y:

  • 6*3+2y=30 ⇒ 2y= 30- 18 ⇒ 2y= 12 ⇒ y=6

finally, x+y

  • x+y= 3+6= 9
User Dmitry Nikiforov
by
5.8k points