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3х – у = 9 - 3х + 5у = -3I need to solve for x and y

User Kashana
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1 Answer

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3х – у = 9 ......................... equ 1

- 3х + 5у = -3 ......................equ 2

equ 1 + equ 2 :

3x + -3 x - y + 5y = 9 + -3

4y = 6

Divide both sides by 4, we have:

y = 6/ 4= 3/ 2 = 1.5

Put y = 3/2 in equ 1, we have

3 x - y = 9 ,

3x - 3/2 =9,

3x = 9 + 3/2

3x = 18/2 + 3/2 = 21/2

3 x = 21/2

Divide both sides by 3,

x = 21/6 = 7/2 = 3.5

Conclusion : x = 3.5

y = 1.5