Answer:
cos(a + b) = 
Step-by-step explanation:
cos(a + b) = cos(a).cos(b) - sin(a).sin(b) [Identity]
cos(a) = 
cos(b) = 
Since, terminal side of angle 'a' lies in quadrant 3, sine of angle 'a' will be negative.
sin(a) =
[Since, sin(a) =
]
= 
= 
Similarly, terminal side of angle 'b' lies in quadrant 2, sine of angle 'b' will be negative.
sin(b) =
= 
= 
By substituting these values in the identity,
cos(a + b) = 
= 
= 
= 
Therefore, cos(a + b) = 
Answer:
y=-3/11x+67/11
Step-by-step explanation:
y-8=-5-8/4--7(x--7)
y-8=-3/11(x+7)
11y-88=-3x-21
11y=-3x-21+88
11y=-3x+67
y=-3/11x+67/11
Answer:
B.60 inches
Step-by-step explanation:
you know you can consider two triangles because of the diagonal cut. and the distance wound be √(36²+48²)=60 inches