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
812
Convert 45% into a decimal
45% = 4.5
Multiply 560 by 4.5
560 • 4.5 = 252
Add 252 to 560
560 + 252 = 812
Hope this helps :)
ANSWER
The dot product is 10.
EXPLANATION
The given vectors are (2,4) and (1,2).
If we have the vectors
u=(a,b) and v=(c,d)
Then the dot product of the two vectors is given by

This implies that,

This simplifies to;

Answer: Slope of 2.
Step-by-step explanation:
Start at where the line meets on the y-axis, -7. Then work your way upwards until you see the line align with a value of x, like (1,-5). Then you see a trend of it going up 2 units and over 1. 2/1 or 2 is your slope.
Would the answer be 176? I’m not sure but i’m curious