Answer:
Step-by-step explanation:
In this particular case we have the following system of equations:
y
=
−
3
x
+
4
[
E
q
.
1
]
x
+
4
y
=
−
6
[
E
q
.
2
]
Substituting
[
E
q
.
1
]
in
[
E
q
.
2
]
:
x
+
4
(
−
3
x
+
4
)
=
−
6
Applying the distributive property on the left side:
x
−
12
x
+
16
=
−
6
Simplifying
:
−
11
x
=
−
22
Solving for
y
:
x
=
−
22
−
11
=
2
Substituting
x
=
2
in
[
E
q
.
1
]
:
y
=
−
3
(
2
)
+
4
=
−
2
Therefore
, the solutions are
x
=
2
and
y
=
−
2
Answer:
7.2*10^3.
7,200 in scientific notation, is 7.2*10^3
725/25 = 29
The driver will have to refill the gas tank 29 times during the 725 miles trip.
I hope this helped you! c:
Answer:
The car must drive at 108 km/h to cover the same journey.
Step-by-step explanation:
Given that:
Time taken by bus journey = 45 minutes = 
Speed of bus = 60 km/h
Distance of the journey = Speed * Time
Distance of the journey = 60 * 0.75 = 45 km
The car needs to cover 45 km in 25 minutes.
25 minutes = 
Distance = Speed * Time
45 = 
Speed = 
Speed = 108 km/h
Hence,
The car must drive at 108 km/h to cover the same journey.
I think its 0.156 because / means division