Answer:
x = 1
, y = 3 thus: A is your Anser
Step-by-step explanation:
Solve the following system:
{2 x + y = 5 | (equation 1)
x + y = 4 | (equation 2)
Subtract 1/2 × (equation 1) from equation 2:
{2 x + y = 5 | (equation 1)
0 x+y/2 = 3/2 | (equation 2)
Multiply equation 2 by 2:
{2 x + y = 5 | (equation 1)
0 x+y = 3 | (equation 2)
Subtract equation 2 from equation 1:
{2 x+0 y = 2 | (equation 1)
0 x+y = 3 | (equation 2)
Divide equation 1 by 2:
{x+0 y = 1 | (equation 1)
0 x+y = 3 | (equation 2)
Collect results:
Answer: {x = 1
, y = 3
Answer:
7
Step-by-step explanation:
1. Do 49÷7 to get the average of 7
It would be 8. To solve, look at it like this: 8-b=(-2). I would then look at a number line or create one if your not to sure of yourself. 8-8=0, and then 0-2=-2. 2+8=10 (the numbers you subtracted). So the answer is 10.
Answer:
x = 4
Step-by-step explanation:
-3x + 2 = -10x + 30
Add 10x to both sides and you get
7x + 2 = 30
Subtract 2 from both sides and you get
7x = 28
Divide both sides by 7 to get x by itself and you get
x = 4
Reminder whatever you do to one side you have to do to the other side!
Hope this helps!
Answer:
75,62.5
Step-by-step explanation:
Given that Mr. Dennis gave his class a 20-question multiple choice quiz. The distribution of raw scores had a mean of 15 and a standard deviation of 2.5
If X is the correct questions in the 20 mcq then
X is with mean = 15 and std dev = 2.5
when score is multiplied by 5
random variable now is
Y = 5x
E(Y) = Mean of Y = 
Thus new score out of 100 would have mean = 75 and std deviation = 62.5
