Answer:
59°
Step-by-step explanation:
γ=cos^-1(18^2+22^2-20^2)/2*18*22)=58.99242°
F=x-48 over 4x. I hope that is right :)
I think that the answer could be D
You can solve this one by adding their rates, but you have to invert the numbers they give you to find the rate. Rate is measured in something per unit of time, and "per" indicates division. So the rates are: 1/3 of an hour (Sally) and 1/6 of an hour (Steve). So add the rates: 1/3 + 1/6 = 1/2. (1/3 is 2/6, and 2/6 + 1/6 = 3/6). Since their combined rate is 1/2 of a room in one hour, it takes them two hours to paint the room.
This answer makes sense: It takes Sally three hours by herself; with Steve's help, she's faster, but not THAT much faster, because he's pretty slow. You can often spot-check word problem answers like this by giving it a common sense once-over. If we came up with four hours, that would clearly be wrong: it should take her LONGER if she's getting help.
X=cost per hamburgurs
y=cost per hot dog
200x+150y=1450
200x+250y=1750
we can multiply first equation by -1 and add to 2nd
-200x-150y=-1450
<u>200x+250y=1750 +</u>
0x+100y=300
100y=300
divide both sides by 100
y=3
sub back
200x+150y=1450
200x+150(3)=1450
200x+450=1450
minus 450 both sides
200x=1000
divide both sides by 200
x=5
the cost of a hamburgur is $5
the cost of a hot dog is $3
