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Solve this system of linear equations. Separate

the x- and y-values with a comma.
13x = -21 - 2y
- 15x = 23 + 2y

User XGamerX
by
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1 Answer

5 votes

Answer:

x = -1 , y = -4

Explanation:

Solve the following system:

{13 x = -2 y - 21 | (equation 1)

-15 x = 2 y + 23 | (equation 2)

Express the system in standard form:

{13 x + 2 y = -21 | (equation 1)

-(15 x) - 2 y = 23 | (equation 2)

Swap equation 1 with equation 2:

{-(15 x) - 2 y = 23 | (equation 1)

13 x + 2 y = -21 | (equation 2)

Add 13/15 × (equation 1) to equation 2:

{-(15 x) - 2 y = 23 | (equation 1)

0 x+(4 y)/15 = -16/15 | (equation 2)

Multiply equation 2 by 15/4:

{-(15 x) - 2 y = 23 | (equation 1)

0 x+y = -4 | (equation 2)

Add 2 × (equation 2) to equation 1:

{-(15 x)+0 y = 15 | (equation 1)

0 x+y = -4 | (equation 2)

Divide equation 1 by -15:

{x+0 y = -1 | (equation 1)

0 x+y = -4 | (equation 2)

Collect results:

Answer: {x = -1 , y = -4

User Gal Dreiman
by
5.1k points