Question

The hypotenuse of a right triangle is 15ft long. One leg is 3ft shorter than the other. Find the lengths of the legs.
Please someone help me work through this

Answer 1

l^2 + (l-3)^2 = 15^2

Answer 2

15^2=x^2+(x-3)^2

Answer 3

15^2=x^2+x^2-6x+9
15^2=2x^2-6x+9

Answer 4

how do i do this amistre64

Answer 5

well ..... we use the pythag thrm which states:

hyp^2 = leg^2 + other leg^2

15^2 = l^2 + (l-3)^2 from the problem stated agree?

Answer 6

i got x=-9 x=-12 so since there r no - then answer should be 9, 12 right

Answer 7

yes

Answer 8

225 = l^2 + l^2 -6l +9 ; go for broke...

0 = 2l^2 -6l - 216 agree?

Answer 9

yes

Answer 10

factor out the common 2

0 = l^2 -3l -108 ; solve for zeros

Answer 11

what is your favorite way to get the zeros of this quadratic?

Answer 12

?

Answer 13

how do we factor this quadratic?

Answer 14

we can complete the square if you like

Answer 15

or we can use the quadratic formula..

Answer 16

we can use
0=x^2-31x-108

Answer 17

divide both sides by 31

Answer 18

x=3,-3 no -
x=3 x=3?

Answer 19

let me clean this up for you; l looks like '1' but its a letter L

0 = x^2 -3x -108 ; try that :)

Answer 20

divide both sides by 3

Answer 21

x=36 x=33

Answer 22

or is it still 12, 9

Answer 23

108+_____ = x^2 -3x +_____ ; complete the square

108 +9/4 = (x-(3/2))^2 ; sqrt side

+- sqrt(441/4) = x-(3/2) ; +3/2

x = 3/2 +- 21/2

Answer 24

x = 24/2 = 12

or

x = -18/2 = -9; lets assume its |-9| = 9

try them out

does: 15^2 = 12^2 + 9^2 ??

Answer 25

225=144=81
YES

Answer 26

then we found our answers :)

You just have to be more efficient at the quads ... and that takes alot of practice ;)

Answer 27

ok so the answers are 12, 9

Answer 28

yes

Answer 29

if leg = 12; the other leg = (12-3) = 9

Answer 30

ty so much