Question

Solve the systems of equations by elimination.

5x + 2y = 29
5x - 2y = 41

6x + 2y = 20
-6x + 3y = 10

Answer 1

Explanation:

PART 1

5x + 2y = 29 -> eq 1

5x - 2y = 41

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(+) (+) (+)

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=> 10x = 70

=> x = 70/10

=> x = 7

Substituting x=7 in eq 1,

5(7) + 2y = 29

=> 35 + 2y = 29

=> 2y = 29 - 35

=> 2y = -6

=> y = -6/2

=> y = -3

PART 2

6x + 2y = 20 -> eq 1

-6x + 3y = 10

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(+) (+) (+)

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=> 5y = 30

=> y = 30/5

=> y = 6

Substituting y=6 in eq 1,

6x + 2y = 20

=> 6x + 2(6) = 20

=> 6x + 12 = 20

=> 6x = 8

=> x = 8/6

=> x = 4/3