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
<span>Simplifying
6(x + -1) = 9(x + 2)
Reorder the terms:
6(-1 + x) = 9(x + 2)
(-1 * 6 + x * 6) = 9(x + 2)
(-6 + 6x) = 9(x + 2)
Reorder the terms:
-6 + 6x = 9(2 + x)
-6 + 6x = (2 * 9 + x * 9)
-6 + 6x = (18 + 9x)
Solving
-6 + 6x = 18 + 9x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-9x' to each side of the equation.
-6 + 6x + -9x = 18 + 9x + -9x
Combine like terms: 6x + -9x = -3x
-6 + -3x = 18 + 9x + -9x
Combine like terms: 9x + -9x = 0
-6 + -3x = 18 + 0
-6 + -3x = 18
Add '6' to each side of the equation.
-6 + 6 + -3x = 18 + 6
Combine like terms: -6 + 6 = 0
0 + -3x = 18 + 6
-3x = 18 + 6
Combine like terms: 18 + 6 = 24
-3x = 24
Divide each side by '-3'.
x = -8
Simplifying
x = -8</span>
Answer:
0,55
Step-by-step explanation:
The given statement is:
41 fewer than the quantity t times 307 is equal to n.
The equation is given by:
The sum of the areas would be two small squares so no
