Question 1035507
With {{{P(-2,1)}}} , {{{Q(6,1)}}} , {{{R(4,-3)}}} , {{{S(4,1)}}} ,
the {{{red(triangle)}}} and its {{{green(altitude)}}} look like this:
{{{drawing(300,180,-3,7,-4,2,
grid(1),green(line(4,-3,4,1)),
red(line(-2,1,6,1)),
red(line(6,1,4,-3)),
red(line(-2,1,4,-3)),
locate(-2.3,1.5,P),locate(6.1,1.5,Q),
locate(4.1,-3,R),locate(4.1,1.5,S)
)}}}
The length of base PQ is the difference in the x-coordinates of P and Q,
{{{6-(-2)=6+2=8}}} , because the y-coordinates are both the same, {{{(1)}}} .
The height (the length of altitude RS is the difference in the y-coordinates of R and S,
{{{1-(-3)=1+3=4}}} , because the y-coordinates are both the same, {{{(4)}}} .
The area is
{{{base*height/2=8*4/2=highlight(16)}}} .