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If the ends of the base of an isosceles triangle are at (2,0) & (0,1) & the eqn of one side is

x=2,

then the orthocentre of the triangle is

A(3/2, 3/2)
B(5/4, 1)
C(3/4, 1)
D(4/3, 7/12)

...?

Verified Answer :

if O is the orthocenter, O=(xo, yo)
such that xo=(2+0 + 2)/3, so xo= 4/3, so the answer must be

d) (4/3, 7/12)

Answer:

The orthocenter of the triangle is \((\frac{5}{4},1)\) and option b is correct.

Step-by-step explanation:

The ends of the base of an isosceles triangle are at (2,0) & (0,1).

Orthocentre of the triangle is the intersection point of all three altitudes from its vertices.

First find any two altitudes, then find intersection point of altitudes.

The equation of a side is x=2, which is an vertical line. The opposite vertices of this side is (0,1), so the perpendicular line is a horizontal line. The equation of first altitude is

\(y=1\)                              .... (1)

In an isosceles triangle, then attitude is the median of non-equal side. It means the altitude is passing through the midpoint of base side.

\(Midpoint=(\frac{2+0}{2},\frac{0+1}{2})=(1,0.5)\)

Slope of base side is

\(m_1=\frac{y_2-y_1}{x_2-x_1}=\frac{1-0}{0-2}=-0.5\)

The product of slopes of two perpendicular lines is -1.

\(m_1\times m_2=-1\)

\(-0.5\times m_2=-1\)

\(m_2=2\)

The point slope form of a line is

\(y-y_1=m(x-x_1)\)

Where, m is slope.

The slope of second altitude is 2 and it passing through the pint (1,0.5), therefore the equation of second altitude is

\(y-0.5=2(x-1)\)

\(y=2x-1.5\)                ..... (2)

From equation (1) and (2), we get

\(x=\frac{5}{4}\)

\(y=1\)

Therefore the orthocenter of the triangle is \((\frac{5}{4},1)\) and option b is correct.

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