Answer:
D. 
Step-by-step explanation:
In this question, the speed of the dolphin is already given, but the unit is different. The speed of the dolphin is given as 40 miles per hour and it has to be converted to feet per hour.
We already know that 1 mile = 5280 feet
Then
40 mile = 5280 * 40 feet
= 211200 feet
So the speed in feet per hour will be 211200 feet per hour. I hope the procedure is clear enough for you to understand. You can always use this method for solving similar problems without requiring any help from outside.
The supplement of a 9 degree angle is 171 degrees.
9x-4/x=3 ok first lets get the like terms together! So 9x+1x=10x rewrite 10x-4=3 add 4 to both sides 10x=7 then divide 10 7/10=.7 x=.7
Or you can do it this way
9x-4/x=3 combine like terms so times -4 to both sides 3*-4=-12 rewrite 9x+x=-12 combine like term (still got some) 9x+1x=10x rewrite 10x=-12 divide 10 to both sides -12/10=-1.2 rewrite x=-1.2 (I'm like 95% sure it's this one) hope this helps!!! Have a nice nite (Don't be afraid to ask me about details on this or another question)!!!
