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- 10x - y = 27
- 4x - y = 9
Find the solution of the system equation.

2 Answers

4 votes

Explanation:

-10x - y = 27 ...1

-4x - y = 9 ...2

...1 - ...2

-10x -y - (-4x - y) = 27 - 9

-10x -y +4x + y = 18

-10x + 4x = 18

-6x = 18

x = 18/(-6)

= -3

User Kerri Shotts
by
7.0k points
0 votes

Answer:

x = - 3, y = 3

Explanation:

Given the 2 equations

- 10x - y = 27 → (1)

- 4x - y = 9 → (2)

Multiplying (1) by - 1 and adding to (2) eliminates the term in y

10x + y = - 27 → (3)

Add (2) and (3) term by term to eliminate y

6x = - 18 ( divide both sides by 6 )

x = - 3

Substitute x = - 3 into either of the 2 equations and solve for y

Substituting into (2)

- 4(- 3) - y = 9

12 - y = 9 ( subtract 12 from both sides )

- y = - 3 ( multiply both sides by - 1 )

y = 3

Solution is x = - 3, y = 3

User Majella
by
6.3k points