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:
Option B) The height, in inches, of a typical apple tree
Step-by-step explanation:
Let
x----> the number of years, after the tree was planted
y ---> the height in inches, of a typical golden delicious apple tree
we have
Remember that
The y-intercept is the value of y when the value of x is equal to zero
In this problem
The y-intercept is the height of the tree when it was planted (x=0)
Answer:
x=0.25 or -1/4
Step-by-step explanation:
120x + 21 = -9
120x = -30 (-21 from both sides of equation)
x = -0.25 or -1/4 (divide 120 from both sides of equation)
5 k in miles equals the unit of 3.10686 in miles
