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3 votes
Solve using substitution

y=1/2x
x+4y=18

User Cucurbit
by
5.3k points

1 Answer

2 votes

Answer:

The solution set is (6,3)

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


User Love Gupta
by
6.2k points