Question

What is the length of stack E C with bar on top in the rectangular prism? Round to the nearest tenth of a centimeter.



A.
7.5 cm

B.
9.4 cm

C.
12.6 cm

D.
15.3 cm

Answer 1

@Michele_Laino i got d

Answer 2

we have to compute this:
\[EC = \sqrt {E{G^2} + C{G^2}} = \sqrt {\left( {{8^2} + {5^2}} \right) + {{12}^2}} = ...?\]
since:
\[E{G^2} = {8^2} + {5^2}\]

Answer 3

9.4

Answer 4

oh wait that is what i got

Answer 5

is that right

Answer 6

no, since you wrote EG, whereas we want to know what is EC

Answer 7

oh

Answer 8

hint:
\[EC = \sqrt {E{G^2} + C{G^2}} = \sqrt {\left( {{8^2} + {5^2}} \right) + {{12}^2}} = \sqrt {64 + 25 + 144} = ...?\]

Answer 9

ohhh

Answer 10

okay so before i got 232.36... but now i got 15.26 so it is 15.3

Answer 11

that's right!

Answer 12

yayy

Answer 13

i have one more can you help

Answer 14

ok!

Answer 15

(3 pt)
What is the area of the rectangle? Round to the nearest square inch.



A.
114 in2

B.
108 in2

C.
106 in2

D.
102 in2

Answer 16

i got d

Answer 17

@MCLover1477

Answer 18

we have:
\[AB = \sqrt {B{D^2} - A{D^2}} = \sqrt {{{18}^2} - {6^2}} = ...?\]

Answer 19

we have to compute that first

Answer 20

288 then squared is 17

Answer 21

then 17 times 6 is 102

Answer 22

because area of rectangle= bh

Answer 23

wait, we have a triangle, so the area is:
(17*6)/2=...?

Answer 24

sorry we have a rectangle, so you are right!

Answer 25

one more

Answer 26

area is 102 in^2

Answer 27

ok! I'm ready!

Answer 28

sorry i cant help right now im a little busy sorry

Answer 29

What is the area of the equilateral triangle? Round to the nearest square centimeter.

cm2
Equilateral triangle A B C with side length of eight centimeters

Answer 30

you dont need the pic. each side is 8

Answer 31

do you know the Heron's formula?

Answer 32

no

Answer 33

if not, look at this drawing:

Answer 34

we have to compute this, first:
\[CH = \sqrt {B{C^2} - B{H^2}} = \sqrt {{8^2} - {4^2}} = ...?\]

Answer 35

6.9

Answer 36

or 7

Answer 37

it is 7

Answer 38

okay now what

Answer 39

so, the area is:
\[{\text{Area = }}\frac{{{\text{base }} \times {\text{ height}}}}{2} = \frac{{8 \times 6.9}}{2} = ...?\]

Answer 40

or:
\[{\text{Area = }}\frac{{{\text{base }} \times {\text{ height}}}}{2} = \frac{{8 \times 7}}{2} = ...?\]

Answer 41

we can use 7 in place of 6.9

Answer 42

So, what do you get?

Answer 43

28

Answer 44

@Michele_Laino

Answer 45

that's right!

Answer 46

thanks so much

Answer 47

thank you!

Answer 48

ill definitley come to you when i need help!!

Answer 49

ok!