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Solve the system by substitution. Check your solution.

Solve the system by substitution. Check your solution.-example-1
User Joe Almore
by
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1 Answer

3 votes

Answer:

The solution is (9, 126).

Explanation:

Multiply all three terms of the first equation by 100 to remove the decimal fractions. We get:

50x + 25y = 3600

Next, solve the second equatin for y, obtaining y = 16x - 18. Now substitute 16x - 18 for y in 50x + 25y = 3600:

50x + 25(16x - 18) = 3600, or 50x + 400x - 450 = 3600.

Combining like terms leads to: 450x = + 450 + 3600 = 4050

Diving both sides by 450 yields x = 4050/450 = 9.

Then x = 9.

Substituting 9 for x in the second equation yields y = -18 + 16(9) = 126.

The solution is (9, 126).

Check by substituting this result into the first equation:

0.5(9) + 0.25(126) = 36

4.5 + 31.5 = 36 This is true, so the solution (above) is correct.

User Daniyelp
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