Easy question: A train travels 30 miles in 1/3 of an hour. Whats is the trains average speed

90mph

Step-by-step explanation;

if an object travels 30 miles in the first part of an hour, and the speed is constant, then we can assume 30*3=90

in the first third, it went 30 mi, in the second it went 30mi, and in the last part it went 30 mi

30+30+30=90

or you could do 30* the denominator (in this case its 3), so 30*3=90

Sorry if this doesn't make sense, hope it helps though!

this linear equation would have just one solution.

step-by-step explanation:

the reason why this would have one solution is that it is an expression with just one variable. since that variable is not raised to a power, it will always have just one solution.

answer: cos [   arcsin (3/5) - arccos (1/2) ] =

step-by-step explanation: × = 3/5 = 0.6--> x = 36.87 and x = 180 - 36.87 = 143.13 deg

cos y = 1/2 --> y = +- 60 deg a. cos (x - y) = cos (143.13 - 60) = cos 83,13  

=

0.12

b. cos (36.87 - 60) = cos (-23.23) = 0.92