which one?
7/24
24/25
7/25
24/7
2007-01-05 17:41:05 · 8 answers · asked by Chris FIGggggg 1 in Science & Mathematics ➔ Mathematics
The answer is 24/25. Why? Giving you, carefully, EVERY step needed :
(7, 24, 25) is a Pythagorean triplet: 7^2 + 24^2 = 49 + 576 = 625 = 25^2. Therefore it contains a right-angle at the intersection of the sides of length 7 and 24 - a VERY NECESSARY STEP.
Angle z is at the (24, 25) apex, with the longest side (25) the hypoteneuse and 24 therefore the "adjacent side."
Therefore, cos z = "A/H" = 24/25. QED.
(gamefreak, you didn't PROVE that the triangle contained a right angle, and therefore that your use of the term "hypoteneuse" was justified.)
Live long and prosper.
2007-01-05 17:55:18 · answer #1 · answered by Dr Spock 6 · 0⤊ 0⤋
in the right-angled triangle XYZ,XY=7,ZX=24 andYZ=25
Therefore cos z=Base/Hypotenuse=ZX/YZ=24/25
2007-01-06 04:04:51 · answer #2 · answered by alpha 7 · 0⤊ 0⤋
i'm gonna say 24/25:
adjacent(zx) / hypotenuse(yz) = 24/25
Jeevan25, you've used incorrect sides within the law of cosines
2007-01-06 01:54:04 · answer #3 · answered by gamefreak 3 · 0⤊ 0⤋
it is no doubt, 24/25. Because cos = adjacent/hypotenuse. Draw a triangle and it will be more clear to you. Best of luck.
2007-01-06 02:13:49 · answer #4 · answered by mani 2 · 0⤊ 0⤋
Sorry that I don't have my graphing calculator to check this one out; forgive me if I am wrong.
Solve the system, I get z = sqrt (600/7) which is approximately 9.1 or so.
cos(9.1) is about 24/25.
Answer: 24/25
2007-01-06 01:58:55 · answer #5 · answered by K.G. 2 · 0⤊ 1⤋
x=7/y
z*(7/y)=24 then y=7*z/24
so (7*z/24)*z=25
z^2=25*24/7=85.714
z=9.2582
if z is in radians then cos z=0.98697
if z is in degrees then cosz=0.999996
i think that the closest one of your choices to my answer is 24/25=0.96
2007-01-06 02:04:20 · answer #6 · answered by laila 2 · 0⤊ 1⤋
xy = 7.........(1)
zx = 24.......(2)
divide the equation (1) by (2)
y/z = 7/24 => z/y = 24/7
also zy = 25,
multiply- (z/y) * (zy) = z^2
z^2 = 600/7
z= 9.26(app)
cos(9.26) = 0.9864 = 24/25(approximation range)
2007-01-06 02:04:43 · answer #7 · answered by Sayan 2 · 0⤊ 1⤋
XY^2 = XZ^2 + YZ^2 - 2(XZ)(YZ)CosZ
CosZ = (XZ^2 + YZ^2 -XY^2) / (2(XZ)(YZ))
= (49 + 625 - 576) / (2(7)(24))
= 98 / 336
CosZ = 7/24
2007-01-06 01:56:18 · answer #8 · answered by Anonymous · 0⤊ 1⤋