Question

The length of a rectangle is 2 meters more than its width.If the area is 63 meters,what are the length and width?

Answer 1

Area = LW; L=W+2

63 = (W+2)(W)

63 = W^2 + 2W

W^2 +W - 63 = 0

so far so good?

Answer 2

yes

Answer 3

the fastest way to solve a quadratic is with the quadratic formula, do you know the quadratic formula?

Answer 4

not really

Answer 5

Do you know how to "complete the square"? which is the long proof for the quad formula?

Answer 6

no

Answer 7

which one would you like to learn?

Answer 8

the fastest way

Answer 9

lol.... good answer

Answer 10

the quad formula is:

-(middle) +- sqrt(middle^2 - (4)(first)(last))
--------------------------------------
2(first)

Lets plug it in :)

Answer 11

(1)W^2 +(1)W - 63

-1 +- sqrt(1^2 -4(1)(-63))
------------------------
2(1)

Answer 12

-1 +- sqrt(1+252)
----------------
2

Answer 13

-1 +- sqrt(253)
--- --------
2 2

now we use a calculator :)

Answer 14

W = about 7.45

Answer 15

we actually get 2 answers, but we can throw out the negative because area is not a negative measurement

Answer 16

L = W+2 so about 9.45 if I did it right :)

Answer 17

becuase I chopped off alot of decimals, we get a skewed result. but its close

Answer 18

so we divided the number above and this is the results

Answer 19

as close as I can get :) barring I havent made any mistakes

Answer 20

so what is the square root of 253

Answer 21

i got 7.95

Answer 22

sqrt(253)=15.905973720586866353745477830541

Answer 23

yes and divided by 2 is 7.95529865

Answer 24

-.5

Answer 25

7.95 + 2 meters is 9.95 correct

Answer 26

still need to take away .5 from 7.955.......

Answer 27

where did -5 come from

Answer 28

-1 +- sqrt(253)
--- --------
2 2

the first part here is -1/2

Answer 29

ohhhhhh.....ok.......i see

Answer 30

so what does the final answer look like

Answer 31

itll probably include a radical sign for an eexat nswer; but the best I can do with an estimate is:

W=about 7.45 and L=about 9.45

Answer 32

ok

Answer 33

can you help me with another one

Answer 34

i dunno, my computer is slowing down something feirce. try it in another question post; and ill see what i can do

Answer 35

ok

Answer 36

I know...iknow..... i see where I messed up.

A=63; L=9 and W=7 i lost a "2" in the equation somewhere lol...

w^2 +[2]w -63 = 0 <---THAT ONE!!

-2/2 + sqrt(4 - (4)(1)(-63))/2

-1 + sqrt([252] +4)/2 <-AND I forgot how to multiply

-1 + sqrt(256)/2

-1 + 16/2

-1 + 8

W = 7

L= W+2 = 7+2 = 9

Area = 9(7) = 63

Are ya happy now :)