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2 years ago

Solve the system of equations using the substitution method.

Mathematics

1 answer:

Mademuasel [1]2 years ago

3 0

Answer:

x = -2.

y = 3.

Step-by-step explanation:

If y = 3x + 9

Substitute this value for y in the first equation.

4x + 5(3x + 9) = 7

4x + 15x + 45 = 7

19x = 7 - 45

19x = -38

x = -38/19

x = -2.

with this value of x, substitute -2 in the second equation

y = 3(-2) + 9

y = -6+9

y = 3.

check if your values are all correct

4(-2) + 5(3) = 7

-8 + 15 = 15 - 8 = 7

Correct!

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I don't see this answer as I'm going to rationalize the denominator.

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