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4 votes
Rewrite the equation of the circle (x + 2)^2 + (y + 5)^2 = 9 in general form.

2 Answers

4 votes

Answer:

x^2+y^2+4x+10y+20=0

Explanation:

(x+2)^2+(y+5)^2=9

x^2+4x+4+y^2+10y+25-9=0

general form: x^2+y^2+4x+10y+20=0

User Arik Segal
by
4.7k points
7 votes

Answer:

x² + 4x + y² + 10y + 20 = 0

Explanation:

Step 1: Expand (x + 2)²

x² + 2x + 2x + 4 + (y + 5)² = 9

Step 2: Combine like terms

x² + 4x + 4 + (y + 5)² = 9

Step 3: Expand (y + 5)²

x² + 4x + 4 + y² + 5y + 5y + 25 = 9

Step 4: Combine like terms

x² + 4x + 4 + y² + 10y + 25 = 9

Step 5: Move 9 over

x² + 4x + 4 + y² + 10y + 25 - 9 = 0

Step 6: Combine like terms

x² + 4x + y² + 10y + 20 = 0

User Rmb
by
4.8k points