Answer:
i could be wrong but i think its x=3 :(
Step-by-step explanation:
Answer:
Her usual driving speed is 38 miles per hour.
Step-by-step explanation:
We know that:
In which s is the speed, in miles per hour, d is the distance, in miles, and t is the time, in hours.
We have that:
At speed s, she takes two hours to drive. So
However, on one particular trip, after 40% of the drive, she had to reduce her speed by 30 miles per hour, driving at this slower speed for the rest of the trip. This particular trip took her 228 minutes.
228 minutes is 3.8 hours. So
So
Her usual driving speed is 38 miles per hour.
Answer:
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mechanism.
Answer:
y
=
4
(
1
2
)
x
Explanation:
An exponential function is in the general form
y
=
a
(
b
)
x
We know the points
(
−
1
,
8
)
and
(
1
,
2
)
, so the following are true:
8
=
a
(
b
−
1
)
=
a
b
2
=
a
(
b
1
)
=
a
b
Multiply both sides of the first equation by
b
to find that
8
b
=
a
Plug this into the second equation and solve for
b
:
2
=
(
8
b
)
b
2
=
8
b
2
b
2
=
1
4
b
=
±
1
2
Two equations seem to be possible here. Plug both values of
b
into the either equation to find
a
. I'll use the second equation for simpler algebra.
If
b
=
1
2
:
2
=
a
(
1
2
)
a
=
4
Giving us the equation:
y
=
4
(
1
2
)
x
If
b
=
−
1
2
:
2
=
a
(
−
1
2
)
a
=
−
4
Giving us the equation:
y
=
−
4
(
−
1
2
)
x
However! In an exponential function,
b
>
0
, otherwise many issues arise when trying to graph the function.
The only valid function is
y
=
4
(
1
2
)
x
Answer: 51 uinits
The three numbers are x , x + 21 and x + 27.
The greatest of the 3 numbers is x + 27, so x + 27 has to be the hypotenuse.
----------------------------------------------
Pythagoras Theorem
----------------------------------------------
a² + b² = c²
x² + (x+21)² = (x+27)²
x² + x² + 42x + 441 = x² + 54x + 729
x² - 12x -288 = 0
(x - 24)(x + 12) = 0
x = 24 or x = -12 (rejected, length cannot be negative)
----------------------------------------------
Find hypotenuse
----------------------------------------------
Hypotenuse = x + 27 = 24 + 27 = 51 units
-----------------------------------------------
Answer: 51 units
----------------------------------------------
