Ok so in order to do this, you have to set up an equation. Let's make a=the score of the first test and b=the score of the second test. (You can choose different variables, it doesn't matter.) It says the sum of the two equals 170. So, a+b=170. It also says that the score of the first was 6 less than the second. This can be shown as a=b-6. Now you can plug this in for a in your original equation. It will look like:
(b-6)+b=170
You can solve for b.
2b-6=170
2b=176
b=88
Since you want a, plug into either equation for b. I'll use the second one.
a=88-6
So, a=82
Answer:
19
Step-by-step explanation:
f(-7) = 4(-7) + 9
-28 + 9
= 19
Answer:
Mean = 10.2
Standard deviation = 4.0
Step-by-step explanation:
The average age = mean age
Mean = (16 + 10 + 5 + 7 + 13)/5
Mean = 51/5 = 10.2
What is the standard deviation will be square root of variance
(16 - 10.2) + (10 -10.2) + (5-10.2) + (7-10.2)+( 13-10.2)
5.8 + 0.2 -5.2 - 3.2 + 2.8
Square each number
33.64 + 0.04 + 27.04 + 10.24 + 7.84
Variance = 78.8/5 = 15.76
Standard deviation = 3.969 = 4.0
Answer:
A
Step-by-step explanation:
Between 4 and 5 where the vertex is. The axis of symmetry is a line going through the vertex. For a while it will be of the form x = a
In this case, the axis of symmetry is x = 4.5
