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
25 hope it helps have a great day :)
Answer: 38 feet.
Step-by-step explanation:
The equation of motion of a body thrown vertically upwards:
,
Substitute in formula (1) the value t=2 c:
You can convert the fraction to a decimal form.
7/9 is .778
.778 is greater than .6
The surface area<span> of a right </span>prism<span> can be calculated using the following formula: SA 5 2B 1 hP, where B is the </span>area<span> of the base, h is the height of the </span>prism<span>, and P is the perimeter of the base. The </span>lateral area<span> of a figure is the </span>area<span> of the non-base faces only.</span>
