Q21 of 184 Page 10

Find the area of the triangle whose vertices A, B, C are (3, 4) (-4, 3), (8, 6) respectively and hence find the length of the perpendicular from A to BC.

Given: A triangle whose vertices A (3, 4) B(-4, 3), C(8, 6)


To find: Find the area of Triangle and length of AD



Area of triangle =


Then,


Area of triangle ABC =


=


=


= 4 square units


We need to find the length of AD on BC


Hence, We need to find the slope first,


The slope


Now the slope of BC = = 5


If AD perpendicular BC then the slope of AD is


Therefore, The equation of is (y - y1) = m(x - x1)


(y + 1) = (x - 5)


5y + 5 = - x + 5


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