The lengths of two sides of a triangle are shown below: Side 1: 3x2 - 4x - 1
Side 2: 4x - x?.5
The perimeter of the triangle is 5x3 - 2x² + 3x - 8.
Part A: What is the total length of the two sides, 1 and 2 of the triangle? (4 points)
Part 8: What is the length of the third side of the triangle? (4 points)
Part C. Do the answers for Part A and Part B show that the polynomials are closed under addition and subtraction? Justify your answer.

help ASAP

Hmm

Step-by-step explanation:

wheres graph

step-by-step explanation:

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.