D=t/3
12=t/3
×3 ×3
___________
36=t
So the answer is D.) 36 kilometers
A square rotated about its center by 360º maps onto itself at 4 different angles of rotation. You can reflect a square onto itself across 4 different lines of reflection.
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
Answer:
y = 9
Step-by-step explanation:
y-y1 = m(x-x1)
m is the slope =y2-y1/x2-x1=9-9/-2-3=0
pick any number out of the given two for (x1, x2)
y-9 = 0*(x-3) so
y-9 = 0 add 9 to both sides
y = 9
