Find the point of intersection, if any , between each circle and line with the equations given?
x^2 + y^2 = 25: y = x
(x+4)^2 + (y-3)^2 = 25: y = x + 2
(x+4)^2 + (y-3)^2 = 25: y = x + 2 sub the second equation into the first for y
(x + 4)^2 + ( x + 2 - 3)^2 = 25
(x + 4)^2 + (x - 1)^2 = 25 expand the left side
x^2 + 8x + 16 + x^2 - 2x + 1 = 25 simplify
2x^2 + 6x + 17 = 25 subtract 25 from both sides
2x^2 + 6x - 8 = 0 divide through by 2
x^2 + 3x - 4 = 0 factor
(x - 1) ( x + 4) = 0 and setiing each factor to 0, we have that x = 1 and x = -4
So when x = 1, y= 1 + 2 = 3 and when x = -4, y= -4 + 2 = -2
So....the intersection points are (1, 3) and ( -4, -2)
x^2 + y^2 = 25: y = x
Put the second equation into the first for y and we have
x^2 + x^2 = 25
2x^2 = 25 divide both sides by 2
x^2 = 25/2 take the square root of both sides
x^2 = [ +/-] 5/sqrt( 2)
And since x = y the intersection points are :
(5/sqrt(2), 5/sqrt(2) ) and (-5/sqrt(2), -5/sqrt(2) )
(x+4)^2 + (y-3)^2 = 25: y = x + 2 sub the second equation into the first for y
(x + 4)^2 + ( x + 2 - 3)^2 = 25
(x + 4)^2 + (x - 1)^2 = 25 expand the left side
x^2 + 8x + 16 + x^2 - 2x + 1 = 25 simplify
2x^2 + 6x + 17 = 25 subtract 25 from both sides
2x^2 + 6x - 8 = 0 divide through by 2
x^2 + 3x - 4 = 0 factor
(x - 1) ( x + 4) = 0 and setiing each factor to 0, we have that x = 1 and x = -4
So when x = 1, y= 1 + 2 = 3 and when x = -4, y= -4 + 2 = -2
So....the intersection points are (1, 3) and ( -4, -2)