Answer:
I think the answer is $4.92.
Step-by-step explanation:
Although the answer seems a little unreasonable, I think this is the answer:
$82 * 60% = $49.2
49.2 * 10% = $4.92
Please mark brainliest if correct!!!!!!!!!!!!!!! have a nice day!!
Step-by-step explanation:
2x - 3y - 2z = 4
[2] x + 3y + 2z = -7
[3] -4x - 4y - 2z = 10
Solve by Substitution :
// Solve equation [2] for the variable x
[2] x = -3y - 2z - 7
// Plug this in for variable x in equation [1]
[1] 2•(-3y-2z-7) - 3y - 2z = 4
[1] - 9y - 6z = 18
// Plug this in for variable x in equation [3]
[3] -4•(-3y-2z-7) - 4y - 2z = 10
[3] 8y + 6z = -18
// Solve equation [3] for the variable z
[3] 6z = -8y - 18
[3] z = -4y/3 - 3
// Plug this in for variable z in equation [1]
[1] - 9y - 6•(-4y/3-3) = 18
[1] - y = 0
// Solve equation [1] for the variable y
[1] y = 0
// By now we know this much :
x = -3y-2z-7
y = 0
z = -4y/3-3
// Use the y value to solve for z
z = -(4/3)(0)-3 = -3
// Use the y and z values to solve for x
x = -3(0)-2(-3)-7 = -1
Solution :
{x,y,z} = {-1,0,-3}
<span>Find the wind speed and the plane's airspeed.
:
Let s = speed of the plane in still air
Let w = speed of the wind
then
(s-w) = plane speed against the wind
and
(s+w) = plane speed with the wind
:
Change 3 3/8 hrs to 3.375 hrs
:
The trips there and back are equal distance, (1890 mi) write two distance equations
dist = time * speed
:
3.375(s-w) = 1890
3.0(s + w) = 1890
:
It is convenient that we can simplify both these equations:
divide the 1st by 3.375
divide the 2nd by 3
resulting in two simple equations that can be used for elimination of w
s - w = 560
s + w = 630
----------------adding eliminates w, find s
2s = 1190
s =
s = 595 mph is the plane speed in still air
Find w
595 + w = 630
w = 630 - 595
w = 35 mph is the wind spee</span>
Answer:
22
Step-by-step explanation:
