Which set of integers does NOT represent the lengths of the sides of a triangle? A. (4,7,9)
B. (6,6,11)
C. (9,10,11)
D. {4,8,12)

3. parallelogram

step-by-step explanation:

we turn each of our sides into direction vectors

ab=b-a=(3 - 7, 1 - 0) = (-4, 1)

bc=c-b=(1,6)

cd=d-c=(4,-1)

da=a-d=(-1,-6)

we see how the opposite sides have negated direction vectors; this is characteristic of a parallelogram.   we have congruent sides ab=cd and bc=da with unequal lengths because 1^2+6^2 is different from (-4)^2+1^2.   so it's not a square or a rhombus.  

we check the dot product of direction vectors of adjacent sides.   we have

ab dot bc = -4(1) + 1(6) = 2

that's not zero so the sides are not perpendicular.   we've ruled out rectangle.

the direction vectors indicate two pairs of congruent parallel sides, so we choose parallelogram over trapezoid.

tangent

step-by-step explanation:

- (2, -7)

- lines r and s and lines t and u must be parallel

3/20

step-by-step explanation:

well, there are 20 outcomes, and 3 of them you want. so, 3/20