Answer:

Step-by-step explanation:
Given information: |a| = 80, |b| = 50, the angle between a and b is 3π/4.
We need to find the dot product a · b.
The formula of dot product is

where, θ is the angle between a and b.
Substitute the given values in the above formula.


![[\because \cos (\pi-\theta)=-\cos \theta]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%5Ccos%20%28%5Cpi-%5Ctheta%29%3D-%5Ccos%20%5Ctheta%5D)


Rationalize the above equation.



Therefore, the value of a · b is
.
4n - 9 + 3n + 5 + n = 68
combine like terms
8n - 4 = 68
addition property of equations
8n = 72
division property of equality
n = 9
SIDES:
n = 9
3n + 5 = 32
[ 3(9) + 5 = 32 ]
4n - 9 = 27
[ 4(9) - 9 = 27 ]
Answer correct or incorrect
Answer:
4
Step-by-step explanation:
It is. I just know it lol