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14 votes
14 votes

4x + 2x = 20 \\ x + 3x = 50
simotenus equation ​

User Paul Schreiber
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1 Answer

16 votes
16 votes

Answer:

I think there is an error in the question, I assume it reads:

4x+2y=20

x+3y=50

If not, please make appropriate corrections to the question.

Answer: x=-4, y=18

Explanation:

4x+2y=20

Simplify, divide by two,

2x+y=10.....................(1)

x+3y=50....................(2)

Multiply (2) by 2

2x+6y=100 ....................(2a)

Subtract (1) from (2a)

2x+6y - (2x+y) = 100 - 10

5y = 90

y=18..............................(3)

Substitute (3) into (1)

2x+(18)=10

2x = 10-18 =-8

x=-4 ............................(4)

Substitute (3) and (4) into (1) for verification

2x+y = 2(-4)+18 = 18-10 = 10 checks.

Substitute (3) and (4) into (2) for verification

x+3y=-4+3(18) = -4+54 = 50 checks.

Have a nice day!

User Bendemann
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3.3k points