now, notice those triangles
the first one, has tickmarks on the upper sides, meaning those two
sides are equal for both triangles
also tickmarks on the angle atop, those two are also equal,
but
notice, both are sharing the middle segment
so the length of that side for both, is also the same,
thus
the triangles are congruent by SAS
now on 2)
tickmarks on two angles,
then again, they're sharing the middle segment
thus
congruence by ASA
what the dickens all that means?
it means that for both triangles, the sides at the bottom,
are also equal, that is
x+2 = 12
solve for "x"
