Answer:
C
Step-by-step explanation:
The difference formula for cosine is
cos(x - y) = cosxcosy + sinxsiny
Consider
cos75 = cos(120 - 45)°, then
cos(120 - 45)°
= cos120°cos45° + sin120°sin45° → C
14/5 = 2.8 yds
14/5 yds is longer then 1.7 yds
Solve simultaneously.
4x - y = 8
6x + y = 2
Multiply top equation by 6, and bottom equation by 4, to eliminate x, so that we can find y.
~
24x - 6y = 48
24x - 4y = 8
Subtract top from bottom to form one equation.
~
-2y = 40
Therefore y is 20.
Put y back in to an equation, such as 4x - y = 8.
~
4x - 20 = 8
4x = 28
x = 7
143 / 6x+12 = 132 / 72
143 / 6x+12 = 11 / 6
crossmultiply:
66x + 132 = 858
66x = 726
x = 11
Answer:
1. (2,2)
2. (-20, -1)
3. (4,3)
Step-by-step explanation:
See attached images