4./3
find the sine and the cosine of 309,

sin(309) = 0.902 cos(309) = 0.432

Explanation:

We can find the nearest possible value and can approximate them for our answer.

now, nearest value possible can be considered 307 in case of 309 angle as 307 can be written as 360-53

and we know the values of sin(360) , cos (360) and sin(53) , cos (53) and the formula to be used is

sin(A-B) = sinAcosB - cosAsinB and

cos(A-B) = cosAcosB + sinAsinB.

Taking A as 360 and B as 53

and substituting values, we get ,

sin(A-B) = (3/5)*0.9 - 1*4/5 = approx 0.902 for sin(309) and

cos(A-B) = 1*3/5 + 4/5*0.9 = approx 0.432 for cos(309).

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer