In the expression 2x - 8 what is x referred to as? 1. coefficient
2. variable
3. constant

Which is NOT an equation?

1. 5 - 4x
2. 6x - 5 = 8
3. x/3 + 9 = -1

Step-by-step explanation:

A) 2x - 8

x is called variable

Option 2

B) 5 - 4x  is not a equation

Option 1

d) -1

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.