Question

I need some help.. I've already done these problems and i got them back and they need fixed.. will someone please help me

Answer 1

what are they?

Answer 2

on these three i need to find the surface area

Answer 3

for the first one we have 4 triangles and a square. the area of a triangle is
.5(base)(height) and the area of a square is (base)^2

Answer 4

so we have 4(.5)(base)(height)+b^2

Answer 5

well i redid the first one and i got 103.47

Answer 6

=2(base)(height)+(base)^2=2(4.2)(10)+(4.2)^2 is this what you did?

Answer 7

yea

Answer 8

I got 101.64

Answer 9

oh yeah that's what i meant..

Answer 10

the second we have 4 triangles

Answer 11

so we have 4 times .5(b)(h) since there are all congruent triangles

Answer 12

=2bh

Answer 13

=2(15)(9)=270

Answer 14

it looks like you got a check mark on that one and the answer was 67.5?

Answer 15

yea.. all the ones i post need fixed

Answer 16

k

Answer 17

does everything make sense so far?

Answer 18

yeah

Answer 19

ok lets look at the last one

Answer 20

6 times .5bh

Answer 21

yes there are 6 triangles and then there is that hexagon hex means 6 right?

Answer 22

yea

Answer 23

lets look at the triangles first the base 6 and we need to find the height

Answer 24

thats if we look at one traingle

Answer 25

if we divide a triangle and half we can from a right triangle so we can use the Pythagorean thm the hyp is 12 and if we divide the base in half the base is 3 or our newly formed triangle so we can find the height of the triangle let's call it h. we have 3^2+h^2=12^2 implies h=sqrt(135). so the area of the whole traingle is .5(6)(sqrt(135)
since we have 6 trangles we have this area times 6 so this equals 18(sqrt(135))
but now we need to find the area of the hexagon

Answer 26

if we draw two vertical lines from one vertex to another and one horizontal line from one vertex to another we would form 2 rectangles and 4 traingles

Answer 27

looking at one triangle we see that the hyp is 6 and we know that the legs are equal. so we have b^2+b^2=6^2 imples 2b^2=36 implies b^2=18 implies b=sqrt(18) so the area of the triangle is .5(sqrt18)(sqrt(18)=.5(18)=9 since we have 4 of these triangles then we multiply the 9 by 4 =36
now we need to find the area of the rectangles we know 1 side =6 so we need find the length of the other side that runs perpendicular to it

Answer 28

but we found that when we were finding the legs of the triangle above
so the side running perpendicular to the 6cm side has length sqrt(18) so the area of the rectangle is (6)sqrt(18) but since we have 2 we multiply by 2 giving us 12sqrt(18)
now we add all of our areas together

Answer 29

so we have the area of the 6 triangles is 18sqrt(135)
and we have the area of the hexagon is 12sqrt(18)+36
the total surface area is 18sqrt(135)+12sqrt(18)+36

Answer 30

so 974.22

Answer 31

i got 296.05

Answer 32

i did my math wrong..

Answer 33

but thank u

Answer 34

that last problem was really long I hope i'm right lol

Answer 35

can help me with some more

Answer 36

more surface area?

Answer 37

no volume

Answer 38

ok i will look at one more and then i have to leave

Answer 39

the first three are finding volume

Answer 40

ok the first one we need to find the area of the base and multiply by the height of the solid

Answer 41

the area of the base is .5(b)(h)=.5(6)(8)=24
the height of the solid is 10
so 24(10)=240

Answer 42

the second one you shouldnt had divided by 3 it should had been 2

Answer 43

the last one you set it up right but you should had got 3451.04

Answer 44

okay thank you

Answer 45

np i hope i was a help

Answer 46

ur were