I pretty sure it (B) sorry if I’m wrong
Okay,
so first you gotta know that cos(90-x) is equal to sinx and sin(90-x) is equal to cosx!!
Now all you gotta do is replace the cos(90-x) to sinx in the numerator and sin(90-x) to cosx in the denomenator inorder to make the numerator all into sin and denomenator all into cos.
After that, open up the brackets and solve...
At the end you'll hopefully get something like this :( 1+sin90 ÷ 1+cos90 )
And since sin90 is 1 (put it in the calculator!) and cos90 is 0, you'll get 2÷1 which is equals to 2!!
Hope this helped! :)
Answer:
a. 47
b. 87
c. 127
Step-by-step explanation:
Assume a total of 4 exams ( first 3 plus a final)
Let final score be X,
Hence, average score = (85 + 71 + 77 + x) / 4 = (233 + x) / 4
a) to get a C, the average score must be 70
70 = (233 + x) / 4
(233 + x) = 70 (4) = 280
x = 280 - 233 = 47 (Ans)
b) to get a B, the average score must be 80
80 = (233 + x) / 4
(233 + x) = 80 (4) = 320
x = 320 - 233 = 87 (Ans)
c) to get a A, the average score must be 90
90 = (233 + x) / 4
(233 + x) = 90 (4) = 360
x = 360 - 233 = 127 (Ans)
We know that 3 point can creating always a plane
so from this result the right choice is A. so is true
Since y must equal both 3x+2 and x-4, we deduce that 3x+2 and x-4 must equal each other. So, we have