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2 years ago

Solve 3x – ly= 11 and -2x – 4y=-26 by elimination

Mathematics

1 answer:

Ede4ka [16]2 years ago

7 0

Answer:

(5, 4 )

Step-by-step explanation:

Given the 2 equations

3x - y = 11 → (1)

- 2x - 4y = - 26 → (2)

Multiplying (1) by - 4 and adding to (2) will eliminate the y- term

- 12x + 4y = - 44 → (3)

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

- 14x + 0 = - 70

- 14x = - 70 ( divide both sides by - 14 )

x = 5

Substitute x = 5 into either of the 2 equations and solve for y

Substituting into (1)

3(5) - y = 11

15 - y = 11 ( subtract 15 from both sides )

- y = - 4 ( multiply both sides by - 1 )

y = 4

solution is (5, 4 )

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Answer:

Step-by-step explanation:

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which simplifies to

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Since it breaks every mathematical rule to have a negative number under an even index radical, we have to deal with that using the imaginary "i". You should know at this point that $i^2=-1$

so we will do a rewrite on that equation above:

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which simplifies further to

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