Question

[4.10] Find the value of y.
A 45, 45, 90 degree right triangle is drawn. One of the 45 degree angles is labeled. The leg adjacent to that 45 degree angle i (4 points)

5

5 times the square root of 2.

10

5 times the square root of 3.

Answer 1

use the facts that
\[\sin(\theta)=\frac{opposite}{hypotenuse}\]
\[\cos(\theta)=\frac{adjacent}{hypotenuse}\]

Answer 2

which one is it?

Answer 3

y is the hypotenuse (longest side in a right angle triangle), and we got the adjacent side, so you can use cos

Answer 4

\[\cos(45)=\frac{5}{y}\]

Answer 5

adjacent is next to and opposite is...well opposite right?

Answer 6

then you know from you r trig circle that 45=pi/4 and cos(45)=sin(45)=root(2)/2
now y=5/(root2/2)=10/root(2) or 5root(2)

Answer 7

yep

Answer 8

but to respect to the angle you know (45 in this case)

Answer 9

so im guessing i set it up like this?\[\frac{ 45 }{ 1 }X \frac{ 5 }{ y }\]

Answer 10

you need the cosine

Answer 11

ur not making sence to me, can you please just tell me the answer?

Answer 12

plz

Answer 13

dude!

Answer 14

i have been warned multiple times that i cant give out answers like that. you need to solve it by yourself, i can just help you understand

Answer 15

it could be clearer to represent cos(45) = root(2)/2 right away

Answer 16

i have no idea what you are trying to explain though! its all like mumbo jumbo!

Answer 17

\[\frac{\sqrt{2}}{2} = \frac{5}{y}\]

Answer 18

now you can solve it

Answer 19

wat bout the sqr root? i dont know how to solve that!

Answer 20

do you know how to solve equations? the root(2) is a constant

Answer 21

so i do 10=sqwrroot 2y?

Answer 22

yep

Answer 23

which is 5?