Use the benchmark 1/2 to compare 5/8 and 2/7

A plane flew 360km in 3 hrs when flying with the wind.With no change in the wind,the return trip took 4 hrs.Find the speed of th

morpeh [17]

Speed of the plane: 250 mph
Speed of the wind: 50 mph
Explanation:
Let p = the speed of the plane
and w = the speed of the wind
It takes the plane 3 hours to go 600 miles when against the headwind and 2 hours to go 600 miles with the headwind. So we set up a system of equations.
600
m
i
3
h
r
=
p
−
w
600
m
i
2
h
r
=
p
+
w
Solving for the left sides we get:
200mph = p - w
300mph = p + w
Now solve for one variable in either equation. I'll solve for x in the first equation:
200mph = p - w
Add w to both sides:
p = 200mph + w
Now we can substitute the x that we found in the first equation into the second equation so we can solve for w:
300mph = (200mph + w) + w
Combine like terms:
300mph = 200mph + 2w
Subtract 200mph on both sides:
100mph = 2w
Divide by 2:
50mph = w
So the speed of the wind is 50mph.
Now plug the value we just found back in to either equation to find the speed of the plane, I'll plug it into the first equation:
200mph = p - 50mph
Add 50mph on both sides:
250mph = p
So the speed of the plane in still air is 250mph.

6 0

2 years ago

If 11 - 3x = x, then 20x=

dimaraw [331]

Answer:

20x = 55

Step-by-step explanation:

First you have to add 3x to both sides of 11-3x=x

$11-3x=x\\+3x=+3x\\11=4x$

Now that you have 11 = 4x you divide 4 on both sides $\frac{11}{4} =\frac{4x}{4}$

11/4 = x

But you can't divide 11 by 4 unless you are looking for the decimal form of 11/4 which is 2.75

so now we take 11/4 or 2.75 depending on if you need your answer in fraction or as a decimal and replace that with x however both will equal the number 55

$20(\frac{11}{4})=55\\20(2.75)=55$

4 0

2 years ago

PLEASE HELP ME ANSWER THIS <br><br> What is the equation for the line?

Kryger [21]

Answer:

y=4x+0 I hope that's what you were looking for

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

10 points! I will thanks, rate, and give best answer!!

vfiekz [6]

Answer: The fourth term is -102

----------------------------------------------

Explanation:

The term after the nth term is generated by this rule $a_{n+1} = -4(a_n) + 2$ which means that we first
Step 1) multiply the nth term ( $a_n$ ) by -4
Step 2) Add the result of step 1 to the value 2 to get the next term in the sequence

Let's follow those steps above to generate the first four terms

The first term is $a_1 = 2$ . In short, the first term is 2

The second term is...
$a_{n+1} = -4(a_n) + 2$
$a_{1+1} = -4(a_1) + 2$
$a_{2} = -4(2) + 2$
$a_{2} = -8 + 2$
$a_{2} = -6$
So the second term is -6

The third term is...
$a_{n+1} = -4(a_n) + 2$
$a_{2+1} = -4(a_2) + 2$
$a_{3} = -4(-6) + 2$
$a_{3} = 24 + 2$
$a_{3} = 26$
The third term is 26

Finally, the fourth term is...
$a_{n+1} = -4(a_n) + 2$
$a_{3+1} = -4(a_3) + 2$
$a_{4} = -4(26) + 2$
$a_{4} = -104 + 2$
$a_{4} = -102$
The fourth term is -102.

4 0

3 years ago

Please help? Thanks if you do cause I really need it :))

krek1111 [17]

The last two would be your answer :)

7 0

2 years ago