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3 votes
Solve the simultaneous equations

X² - xy + 7Y ²=27
x² - y² = 15

User Horatio Alderaan
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1 Answer

26 votes
26 votes

Answer:

Explanation:

We can solve the simultaneous equations by using the substitution method.Firstly, we'll rearrange the second equation so that it's in the form y = mx + c. We can do this by adding 15 to both sides, giving us:y = x² - 15

Now we can substitute this into our first equation:

X² - x(x² - 15) + 7(x² - 15) ²=27

This simplifies to:X² - x³ + 21x² - 105x + 729 = 27

Now we have a cubic equation which we can solve using standard methods.

User Ingulit
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