It means that the two vectors are perpendicular or orthogonal
Answer:

Step-by-step explanation:
We want to find
.
can be written as
, so we can now write our original equation as:
.
We can combine like terms: 
Hope this helps!
73 foot showed.......................
Step-by-step explanation:
cross multiply
2x - 4 = 4 × 5
2x - 4 =20
collect like terms (CLT)
2x = 20 + 4
2x=24
divide both sides by 2
x=12
Answer:
100 packets
Step-by-step explanation:
Given :
Cost = fixed cost + variable cost
Fixed cost = $500
Variable cost = $10
Sales price = $15
Let :
Number of packets = x
To break even :
fixed cost + variable cost = sales made
500 + 10x = 15x
500 = 15x - 10x
500 = 5x
x = 500 / 5
x = 100
100 packets