Answer:
x=-15, y=25. (-15, 25).
Step-by-step explanation:
2x+3y=45
x+y=10
--------------
x=10-y
2(10-y)+3y=45
20-2y+3y=45
20+y=45
y=45-20
y=25
x+25=10
x=10-25
x=-15
Answer:
81.85%
Step-by-step explanation:
Given :
The average summer temperature in Anchorage is 69°F.
The daily temperature is normally distributed with a standard deviation of 7°F .
To Find:What percentage of the time would the temperature be between 55°F and 76°F?
Solution:
Mean = 
Standard deviation = 
Formula : 
Now At x = 55


At x = 76


Now to find P(55<z<76)
P(2<z<-1)=P(z<2)-P(z>-1)
Using z table :
P(2<z<-1)=P(z<2)-P(z>-1)=0.9772-0.1587=0.8185
Now percentage of the time would the temperature be between 55°F and 76°F = 
Hence If the daily temperature is normally distributed with a standard deviation of 7°F, 81.85% of the time would the temperature be between 55°F and 76°F.
Answer:
z would be at (-6,6)
Step-by-step explanation:
hope that helps
1. A or B
2. C
3. I think B