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Simultaneous eqautions
3x+2y=16
2x+y=9

User Igal
by
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2 Answers

4 votes
multiplying eqn (1) by 2 and eqn (2) by 3 and substracting
6x+4y = 32
6x+3y = 27
we get,
y = 5
putting y = 5 in eqn (2) we get
2x + 5 =9
2x = 9 -5
2x = 4
or x = 2
therefore x = 2 and y =5.
(2,5)
User Vern
by
3.0k points
8 votes

Answer:

(2, 5 )

Explanation:

3x + 2y = 16 โ†’ (1)

2x + y = 9 ( subtract 2x from both sides )

y = 9 - 2x โ†’ (2)

substitute y = 9 - 2x into (1)

3x + 2(9 - 2x) =16

3x + 18 - 4x = 16

- x + 18 = 16 ( subtract 18 from both sides )

- x = - 2 ( multiply both sides by - 1 )

x = 2

substitute x = 2 into (2)

y = 9 - 2(2) = 9 - 4 = 5

solution is (2, 5 )

User Ryan Smith
by
3.7k points