If EF is the perpendicular bisector of CD, find x.

Step-by-step explanation:

A Perpendicular Bisector cuts a segment into two equal parts. We already know that 4x+19 and 6x-7 are both equal.

So then, you would start with 6x-7 = 4x+19.

6x-7 = 4x+19

Subtract -4x from both sides

2x-7 = 19

Add 7 to both sides

2x = 26

Divide both sides by two

x= 13

You only need x, so you're done.

(I'm like 90 percent sure this is wrong man don take my word for it bro).

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.

i think it is 18

step-by-step explanation: