SOLUTION: What point is the intersection of the graphs of x^2 + y^2 = 25 and y = x + 7?

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Question 475399: What point is the intersection of the graphs of x^2 + y^2 = 25 and y = x + 7?

Found 2 solutions by Alan3354, ewatrrr:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Sub for y in the 1st eqn, solve for x.
Repost with your work if you want help.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
What point is the intersection of the graphs:
x^2 + y^2 = 25 circle C(0,0) and radius = 5 (See below)
y = x + 7 Line: Pt(0,7) and Pt(-7,0) on the Line
algebraically: substituting (x+7) for y
x^2 + (x+7)^2= 25
2x^2 +14y + 24 =(2x+6)(x+4) |tossing out x = -3 as Extraneous
x = -4 then y = 3 (y = -4+7)
Graphs: parbola and Line intersect at:(-4,3)

Standard Form of an Equation of a Circle is %28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2
where Pt(h,k) is the center and r is the radius
Standard Form of an Equation of an Ellipse is %28x-h%29%5E2%2Fa%5E2+%2B+%28y-k%29%5E2%2Fb%5E2+=+1+
where Pt(h,k) is the center and a and b are the respective vertices distances from center.
Standard Form of an Equation of an Hyperbola opening right and left is:
%28x-h%29%5E2%2Fa%5E2+-+%28y-k%29%5E2%2Fb%5E2+=+1 where Pt(h,k) is a center with vertices 'a' units right and left of center.
Standard Form of an Equation of an Hyperbola opening up and down is:
%28y-k%29%5E2%2Fb%5E2+-+%28x-h%29%5E2%2Fa%5E2+=+1 where Pt(h,k) is a center with vertices 'b' units up and down from center.
The vertex form of a parabola opening up or down, y=a%28x-h%29%5E2+%2Bk where(h,k) is the vertex.
The standard form is %28x+-h%29%5E2+=+4p%28y+-k%29, where the focus is (h,k + p)
The vertex form of a parabola opening right or left, x=a%28y-k%29%5E2+%2Bh where(h,k) is the vertex.
The standard form is %28y+-k%29%5E2+=+4p%28x+-h%29, where the focus is (h +p,k )