Number of weekend minutes used: x
Number of weekday minutes used: y
This month Nick was billed for 643 minutes:
(1) x+y=643
The charge for these minutes was $35.44
Telephone company charges $0.04 per minute for weekend calls (x)
and $0.08 per minute for calls made on weekdays (y)
(2) 0.04x+0.08y=35.44
We have a system of 2 equations and 2 unkowns:
(1) x+y=643
(2) 0.04x+0.08y=35.44
Using the method of substitution
Isolating x from the first equation:
(1) x+y-y=643-y
(3) x=643-y
Replacing x by 643-y in the second equation
(2) 0.04x+0.08y=35.44
0.04(643-y)+0.08y=35.44
25.72-0.04y+0.08y=35.44
0.04y+25.72=35.44
Solving for y:
0.04y+25.72-25.72=35.44-25.72
0.04y=9.72
Dividing both sides of the equation by 0.04:
0.04y/0.04=9.72/0.04
y=243
Replacing y by 243 in the equation (3)
(3) x=643-y
x=643-243
x=400
Answers:
The number of weekends minutes used was 400
The number of weekdays minutes used was 243
Answer:

Step-by-step explanation:
Hello,


It means that

And we know that

So we got two equations

For 
For 
I assume that we are after two different roots so the solution for p is p=-11
b) 
So a quadratic equation with the expected roots is

Hope this helps.
Do not hesitate if you need further explanation.
Thank you
Answer:
$131.25
Step-by-step explanation:
175×0.25=43.75
175-43.75=131.25
Answer:
radius=3
Step-by-step explanation:
volumes of a cone = 1/3πr²h
12π = 1/3× π × r² × 4
37.7 = 12.6r²/3
cross multiply
37.7×3=12.6r²
113.1=12.6r²
make r² subject of the formula
r²=113.1÷12.6
r²=8.976
r=√8.976
r=2.996
r=3.0 (to the nearest tenth)