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The orthocenter describes the point of concurrency for the lines containing the altitudes of a triangle.
(- 4,- 4)
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 outside the triangle. Therefore, the orthocenter lies outside 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 ST and SR.
Since ST is horizontal, its altitude will be vertical. From the diagram, we can see that OR is a vertical line through x=- 4. Therefore, the equation of the line for the line segment of the altitude is x=- 4.
To find the equation for the second altitude, we need the slope of SR. We can use the Slope Formula and the coordinates of S and R to do this.
Substitute ( - 1,5) & ( - 4,8)
We found that the slope of SR is - 1. 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. -1* m_a = -1 ⇒ m_a = 1 The slope of the altitude is 1. From the diagram, we also know that the altitude passes through the point T(5,5). We will use point-slope form of a line to write its equation. y-y_1=m(x-x_1) Let's substitute 1 for m and ( 5, 5 ) for (x_1,y_1) in the formula.
Substitute values
Distribute 1
LHS+5=RHS+5
This final equation is the equation of the line for the line segment of the altitude.
Finally, we can solve the system of the found equations to find the coordinates of their intersection. x=-4 y=x ⇔ x=-4 y=-4 Therefore, the coordinates of the orthocenter are (- 4,- 4).