MHB Points where a line intercepts a circle

AI Thread Summary
The discussion focuses on finding the intersection points between the line x + 2 and the circle defined by (x + 2)² + y² = 1/2. One point, (-3/2, 1/2), was identified, but the second point remained elusive. A participant clarified that from the equation (x + 2)² = 1/4, two solutions for x can be derived: x = -3/2 and x = -5/2. Consequently, the second intersection point is determined to be (-5/2, -1/2). The thread concludes with both intersection points established.
thazel345
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circle: (x+2)^2+y^2=1/2
line: x+2
iv been able to find one point but can't find the other
work:
2(x+2)^2 =1/2
divide by 2 on both sides
(x+2)^2=1/4
square both sides
x+2=.5
subtract 2
x=-3/2
i used that to find the y but that only gives me one point please help
 
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thazel345 said:
circle: (x+2)^2+y^2=1/2
line: x+2
iv been able to find one point but can't find the other
work:
2(x+2)^2 =1/2
divide by 2 on both sides
(x+2)^2=1/4
square both sides
x+2=.5
subtract 2
x=-3/2
i used that to find the y but that only gives me one point please help

(Wave)

From $(x+2)^2=\frac{1}{4}$ we get that $x+2= \pm \frac{1}{2}$.
So $x_1=\frac{1}{2}-2=-\frac{3}{2}$ and $x_2=-\frac{1}{2}-2=-\frac{5}{2}$.
So we get the points $(x_1, x_1+2)=\left( -\frac{3}{2}, \frac{1}{2}\right)$ and $(x_2, x_2+2)=\left( -\frac{5}{2}, -\frac{1}{2}\right)$.
 
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