Question

Solve the given simultaneous equations : 25x + 30y = 200 ; 30x + 25y = 185
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Answer 1

Solution :

25x + 30y = 200....... eq1

30x + 25y = 185 ......eq2

add eq 1 and 2

25x + 30y = 200

30x + 25y = 185

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55x + 55y = 385 ..eq

divide eq by 55

x + y = 7 ........eq3

subtract eq 1 and 2

25x + 30y = 200

-30x - 25y = 185

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-5x + 5y = 15 ..eq

divide eq by 5

-x + y = 3 .........eq4

Add eq3 and eq4

x + y = 7

-x + y = 3

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2y = 10

y = 10/2

y = 5

y = 5 put in eq3

x + y = 7

x + 15 = 7

x = 7 - 5

x = 2

Value of x is 2 and y is 5