9514 1404 393
Answer:
5
Step-by-step explanation:
Add the latter two equations and you get ...
(a +b) +(a -b) = (7) +(3)
2a = 10 . . . . . . . . . . . . . . . simplify
a = 5 . . . . . . . divide by 2
Do the parentheses first
Since it’s dividing you are supposed to times it
line up your decimals and then multiply like usual, next count how many places after the decimal your problem(s) was and place it to your answer
Answer:
See below in bold.
Step-by-step explanation:
cos 150 = - cos(180 - 150)
= - cos 30
= -√3/2.
sin 150
= sin (180 - 150
= sin 30
= 1/2.