For the first one you would do:
X rad 3=7 divide by rad 3 in both sides and you don’t wanna leave a radical in the denominator so multiply rad 3 in both denom. And numerator and then you get 7rad3/3.
A 30:60:90 triangle always have n:2n:n rad 3 so since 2n=10 you would get n=5 and since BC is n rad3 so you would get 5rad 3.
In a 45:45:90 triangle it is n:n:n rad 2, since AC=3 then AB= 3 and then BC= 3 rad 2
Since AC and AB are congruent you they both would be 12 so it is true.
The answer
f(x) = 0.7(6)x = <span>f(x) = 0.7(6)^x, and </span><span>g(x) = 0.7(6)–x= </span>g(x) = 0.7(6)^-x=1/<span>0.7(6)^x
so </span>
g(x) =1/<span>0.7(6)^x=1 /</span><span><span>f(x)
</span> the relationship between f and g are </span>g(x) =1 /<span>f(x) or </span><span>g(x) . <span>f(x) = 1</span> </span>
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
$24 if it is at the beginning of the day and he is left with $11, and if he spent $13, then 11+13=24
