Answer:
84
Step-by-step explanation:
A=bh/2.
A=(21*8)/2
A=168/2
A=84
Took me a minute to think.
Form ratios.
x, the small triangle, forms a ratio with 6, the big triangle.
The part of the side that is equal(with the dash) that is part of the small triangle
is equal to 6-x, the big triangle.
Yes, you can cross-multiply here!

<em>Now,</em><em> </em>cross multiply.
P.S. Use distributive property.
36-6x = 8x
Add 6x on both sides.
36=14x
Divide by 14 on both sides.
x =

=
7-3=4
4/2=2
The answer is 2
5.00+0.67+0.07 that's it I believe