Remember that

So if
and
, then we know
.
Then use the Pythagorean identity to solve for cosine:

Answer:
18km/h
Step-by-step explanation:
if the riverboat is already going 15 km/h and the current is 3km/h then you should add and you get 18 km/h
The answer is d and because if you divide 15 by 5 it’s 3 so it’s 9
Answer:
x= 20
Step-by-step explanation:
The three angles add to 90 degrees
x+2x+x+10 = 90
Combine like terms
4x+10 = 90
Subtract 10 from each side
4x +10-10 = 90-10
4x = 80
Divide by 4
4x/4 = 80/4
x = 20
Step-by-step explanation:
We dimension of the smallest cube to be made from cuboids of sides 3 m , 4 m and 5 m will be the least common multiple of 3 m, 4 m and 5 m i.e. 60 m
12 cuboidal should be stacked along 5 m edge to 60 m, 15 cuboids should be stacked along 4 m edge and 20. cuboids should be stacked along edge to make a cube of 60 m edge, Hence number of cuboids are 12× 15 ×20=3600
hope it helps