3 years ago

Solve the simultaneous equation 2x - 5y = 9 3x + 4y = 2

Mathematics

1 answer:

lianna [129]3 years ago

8 0

Answer:

x = 2, y = -1.

Step-by-step explanation:

2x - 5y = 9

3x + 4y = 2

Multiply first equation by -3 and the second by 2:

-6x + 15y = -27

6x + 8y = 4 Adding the 2 equations:

23y = -23

y = -1.

Now substitute this value for y in the first equation:

2x - 5(-1) = 9

2x = 9 +5(-1)

2x = 9 - 5

2x = 4

x = 2.

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