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
Attach a pic please
that would help
Answer:
The option on the top right.
Step-by-step explanation:
Because this is to be done asap, I will not take time to explain.
If u mean 4^4 or four to the fourth power then it’s 256
Answer-The vector is
=
7
→
i
−
24
→
j
and the magnitude is
=
25
Explanation:
Let the point
A
=
(
−
2
,
7
)
and
B
=
(
5
,
−
17
)
Then,
−−→
A
B
=
(
5
−
(
−
2
)
−
17
−
7
)
=
(
7
−
24
)
The magnitude of
−−→
A
B
is
∣
∣
∣
∣
∣
∣
−−→
A
B
∣
∣
∣
∣
∣
∣
=
√
(
7
)
2
+
(
−
24
)
2
=
25
Step-by-step explanation:
