The slope of the line is 2/3, so the angle is arctan(2/3) ≈ 33.69°.
1 + tan ² Ф=sec²Ф
1+(12/5)²=sec²Ф
169/25=sec² Ф
sec Ф=⁺₋√(169/25)=⁺₋13/5
sec Ф=1/cos Ф ⇒cosФ=1/sec Ф
cos Ф>0 ⇔ sec Ф>0 ⇔ sec Ф=+ 13/5
cos Ф=1/secФ
cos Ф=1 / 13/5=5/13
we can calculate the sin Ф, with this method.
sin²Ф + cos²Ф=1 ⇒ sin Ф=⁺₋√(1-cos² Ф)
sin Ф=⁺₋√[1-(5/13)²]=⁺₋12/13
like cos Ф>0 and tan Ф>0 ⇒ sin Ф>0 ⇒sin Ф=12/13
answer: d.12/13
other method
tan Ф=sin Ф / cos Ф
12/5=sin Ф / 5/13
sin Ф=(12/5)*(5/13)=12/13
answer: d.12/13
Answer:
27
Step-by-step explanation:
Let <em>g </em>be Gabrielle's age and <em>m </em>be Mikhail's age.
We can turn the statements the problem gives us into mathematical expressions to help us solve.
Gabrielle's age is two times Mikhail's age:
<em>g </em>= 2<em>m</em>
The sum of their ages is 81:
<em>g </em>+ <em>m </em>= 81
This gives us a system of equations that will allow us to solve for Gabrielle's age.
<em>g </em>+ <em>m </em>= 81
(2<em>m</em>)<em> </em>+ <em>m </em>= 81
3<em>m </em>= 81
<em>m</em> = 
<em>m </em>= 27
If we need to solve for Gabrielle's age, we can do the following.
<em>g </em>= 2<em>m</em>
2(27)<em> </em>= <em>g</em>
54 = <em>g</em>
g = 54
Mikhail's age is 27.
Gabrielle's age is 54.