math
posted by Emil on .
I have a triangle in a coordinate system(not native english) i have these three points.
A: 4,2
B:2,1
C: 4,3
How do i get the height of it in relation BC?
And, how do i calculate the total area of the triangle?
Made this atm:
AB:
((2)4)/((1)2) = 2;
y2=2(x1)
y = 2*x;
BC:
(4+2)/(3+1) = 3/2;
y2 = 3/2*(x1);
y = (3/2)*x+1/2;
Took explanation out, it is in another language ;)

If you were finding slope, then you have it upside down.
slope AB = (2 + 1)/(4+2) = 1/6
slope of BC = (3+1)/(4+2) = 4/6 = 2/3
equation of BC
y3 = (2/3)(x4)
3y  9 = 2x  8
2x  3y + 1 = 0
distance from A(4,2) to BC
= 2(4)  3(2) + 1√(2^2 + (3)^2)
= 15/√13