4. three consecutive even integers are such that the sum of the smallest and 3 times the
second is 30 more than twice thee third. find the integers.

Integers are:

14, 16, 18

Step-by-step explanation:

Let three consecutive even integers be:

x          (smallest)

x + 2    (second)

x + 4    (third)

According to given conditions:

x + 3(x + 2) = 30+ 2(x + 4)

By simplifying:

x + 3x + 6 = 30 + 2x + 4

By adding like terms

4x + 6 = 34 + 2x

Now taking terms with x on left side and constants on right

4x - 2x = 34 - 6 (sign of transferred terms will be changed)

2x = 28

Dividing both sides with 2

x = 28/2

x = 14

So the consecutive integers will be:

x = 14

x + 2 = 14 + 2= 16

x + 4 = 14 + 4 = 18

I hope it will help you!

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.

395.84

step-by-step explanation:

2πrh+2πr²

2 (pie)(radius)(height)+2(pie)(radius)^2