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The orthocenter describes the point of concurrency for the lines containing the altitudes of a triangle.
(- 1,5)
Let's begin by drawing the triangle using the given coordinates.
To find the location of the orthocenter, we need to recall two definitions.
Let's draw the altitudes of the vertices of our triangle.
We can see that the altitudes intersect inside the triangle. Therefore, the orthocenter O lies inside the triangle. To find its coordinates, we should determine the equations for two of the altitudes and solve the system of these equations. Let's use the altitudes of AC and AB.
Since AC is horizontal, its altitude will be vertical. From the diagram, we can see that BO is a vertical line through x=- 1. Therefore, the equation of the line for the line segment of the altitude is x=- 1.
To find the equation for the second altitude, we need the slope of AB. We can use the Slope Formula and the coordinates of A and B to do this.
Substitute ( - 3,3) & ( - 1,7)
We found that the slope of AB is 2. The product of the slopes of two perpendicular lines is -1. This allows us to find the slope of the altitude. Let's call it m_a. 2* m_a = -1 ⇒ m_a = - 1/2 The slope of the altitude is - 12. From the diagram, we also know that the altitude passes through the point C(3,3). Let's use point-slope form to find the equation of the altitude.
Substitute values
Distribute - 1/2
LHS+3=RHS+3
a = 2* a/2
Add fractions
Therefore, the equation of the altitude of AB is y=- 12x+ 92.
Finally, let's solve the system of equations we found to find the coordinates of their intersection.
(II): x= - 1
(II): Multiply
(II): Add fractions
(II): Calculate quotient
Therefore, the coordinates of the orthocenter are (- 1,5).