Answer:
A
Step-by-step explanation:
The two equations are similar, because if you multiply the first one by 3 it will be equal to the second one, so when that happens we say that there are infinite solutions.
A=100
b=8
w=108
756 divided by 7=108
Let the time = x
Distance = Speed x time
One train is 75x, the other train 85x
Add together to equal total distance:
75x + 85x = 384
Simplify:
160x = 384
Divide both sides by 160:
x = 384 / 160
x = 2.4 hours
Answer:
-1/2
Step-by-step explanation:
Im not going to go into detail about how to compute sin30 and cos 30, but know that sine and cosine are just the ratios between the sides of a 30-60-90 triangle with a hypothenuse of 1.
With that being said:
sin^2 30 - cos^2 30
= (1/2)^2 - ((sqrt3)/2)^2
= 1/4 - 3/4
= -1/2
The answer is that his average is 75.5 for the second nine weeks