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3 years ago

Solve using substitution y=1/2x x+4y=18

Mathematics

1 answer:

Aleks [24]3 years ago

7 0

Answer:

The solution set is (6,3)

Step-by-step explanation:

Begin by multiplying equation 1 by 2. You'll see why in a moment

2y = 2*(1/2) x

2y = x

Substitute this value into equation 2.

2y + 4y = 18 Combine like terms on the left

6y = 18 Divide both sides by 6

6y/6 = 18/6 Do the division

y = 3

To solve for x just use the top equation

y = 1/2x

3 = 1/2x Multiply by 2

3*2 = x

x = 6

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