Alicia and her friends got out for burgers and and sodas. she is feeling very generous and wants to pay for everyone. the register rings up the meals and coupons below.

alicia $3.83 diego $7.95 carmen $4.32 zac $6.54 the twins $14.89 coupon $7.50

the register gives the total cost as 38.55. estimate the total amount of the bill, by rounding to the nearest dollar, use your answer to determine if the total is reasonable

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.

a variable is any characteristics, number, or quantity that can be measured or counted. a variable may also be called a data item. hope i !