1 and .20 can be your answer i guess.
Answer:
x = -41
y = 9
Step-by-step explanation:
Begin by multiplying the top equation by 2
2x = -8y - 10
The second equation requires a little more care.
Start by moving 10y to the right. Normally the y value is on the left, but we are going to be substituting for 2x.
2x = - 10y + 8
What I've done is not the usual practice, but there is nothing wrong with it.
Now since both right sides are equal to 2x, you can substitute for them
-8y - 10 = -10y + 8 Add 10y to both sides
-8y + 10y - 10 = 8
2y - 10 = 8 Add 10 to both sides
2y = 8+10
2y = 18 Divide by 2
y = 18/2
y = 9
Use the second original equation to solve for x
2x + 10y = 8
2x + 10*9 = 8
2x + 90 = 8 Subtract 20 from both sides
2x = 8 - 90
2x = - 82 Divide by 2
x = -822/2
x = - 41
A = 3b Divide both sides by 3

= b Switch the sides so it's easier to read
b =
Your answer is D.
Explanation
It is the only one that makes sense
<span>Not the mean of the two speeds. The average speed is the totality of the distance divided by the totality of the time. For convenience, let us say that the distance is 1000 miles. Then the total time is
(500 / 55) + (500 / 90) = 14.65 hours
The average speed is 1000 divided by the total time, 68.28 mph.
The reason that the true average speed, 68.28, comes out lower than Mirt's naive value is that you spend more TIME driving at 55 miles per hour than at 90 miles per hour. That reduces that true average speed below the mean of the two speeds.
Here's one for Mirt: let's say you want to complete a trip at an average speed of 60 miles per hour. You go the first half of the distance at 30 miles per hour. How fast would you have to go the second half? (Mirt would say 90, but that is not correct. There is in fact no speed for the second half that could raise your average to 60. Let's say the whole trip is 60 miles and you would like to complete it in one hour, for an average of 60 miles per hour. If you do the first half, 30 miles, at 30 miles per hour, you have used up your whole time and cannot raise your average to 60 no matter how fast you go.)</span>