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(0,0) (8,4) (4,22) what is the orthocenter

User R K Punjal
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1 Answer

4 votes

We have the three vertices of the triangle:

A = (0, 0)

B = (8, 4)

C = (4, 22)

To find the orthocenter, we need to find the intersection point of the altitudes. The altitudes of a triangle are perpendicular lines drawn from each vertex to the opposite side.

First, we need to find the slope of side AB, BC, and CA.

The slope of AB:

m_AB = (4 - 0) / (8 - 0) = 4/8 = 1/2

The slope of BC:

m_BC = (22 - 4) / (4 - 8) = 18 / -4 = -9/2

The slope of AC:

m_AC = (22 - 0) / (4 - 0) = 22/4 = 11/2

Since the slope of the altitude is the negative reciprocal of the slope of the corresponding side, we have:

Slope of altitude from A = -2 (negative reciprocal of AB)

Slope of altitude from B = 2/9 (negative reciprocal of BC)

Slope of altitude from C = -2/11 (negative reciprocal of AC)

Now, let's write the equations of the altitudes using the point-slope form, y - y1 = m(x - x1):

Equation of altitude from A:

y - 0 = -2(x - 0)

y = -2x

Equation of altitude from B:

y - 4 = (2/9)(x - 8)

y = (2/9)x - 16/9 + 4

y = (2/9)x - 16/9 + 36/9

y = (2/9)x + 20/9

Equation of altitude from C:

y - 22 = (-2/11)(x - 4)

y = (-2/11)x + 8/11 + 22

y = (-2/11)x + 8/11 + 242/11

y = (-2/11)x + 250/11

Now, we need to find the point of intersection of these three lines. Solving the system of equations:

-2x = (2/9)x + 20/9

(-2/11)x + 250/11 = (2/9)x + 20/9

From the first equation, multiplying through by 9:

-18x = 2x + 20

-20x = 20

x = -1

Substituting x = -1 into the equation of the altitude from A:

y = -2(-1)

y = 2

Therefore, the orthocenter of the triangle ABC is (-1, 2).

User Nev
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