Answer:
- The system of equations is x + y = 85 and 7/20x+2/5y=31
- To eliminate the x-variable from the equations, you can multiply the equation with the fractions by 20 and multiply the other equation by -7.
- B-She used 60 minutes for calling and 25 minutes for data.
Step-by-step explanation:
It is always a good idea to start by defining variables in such a problem. Here, we can let x represent the number of calling minutes, and y represent the number of data minutes. The the total number of minutes used is ...
x + y = 85
The total of charges is the sum of the products of charge per minute and minutes used:
7/20x + 2/5y = 31.00
We can eliminate the x-variable in these equations by multiplying the first by -7 and the second by 20, then adding the result.
-7(x +y) +20(7/20x +2/5y) = -7(85) +20(31)
-7x -7y +7x +8y = -595 +620 . . . . eliminate parentheses
y = 25 . . . . . . . . simplify
Then the value of x is
x = 85 -y = 85 -25
x = 60
Given diameter 2cm
Find the area of a circle
the formula for area of a circle
A = pi r^2
the diameter is the radius times two
so to find the radius given the diameter 2/2 = 1
radius is 1cm
pi is ~3.14
A = (3.14) * (1)^2
A = (3.14) * 1
A = 3.14
Hope this helps :)
Answer:
If Elizabeth randomly chooses her ride in the morning and in the evening, 2/3 is the probability that she'll use a cab exactly one time
Answer:
10
Step-by-step explanation:
10/-5 = -2
-2+-2 = -4
