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Solve the system of equations algebraically.5x + y = 93x + 2y = 4

User Jerrymouse
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1 Answer

17 votes
17 votes

The solution is (2, -1)

Step-by-step explanation:

5x + y = 9 ....(1)

3x + 2y = 4 ....(2)

Using susbtitution method:

from equation 1, we will make y the subject of formula

y = 9 - 5x

substitute for y in equation 2:

3x + 2(9 - 5x) = 4

3x + 2(9) -2(5x) = 4

3x + 18 - 10x = 4

-7x + 18 = 4

-7x = 4 - 18

-7x = -14

Divide both sides by -7:

-7x/-7 = -14/-7

x = 2

substitute for x in equation (1):

5(2) + y = 9

10 + y = 9

y = 9 - 10

y = -1

The solution (x, y) is (2, -1)

User Viktor Sinelnikov
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