Answer:
Speed of plane in still air: 490 mile/hour
speed of wind: 70 mile/hour
Step-by-step explanation:
still speed = x wind speed = w
with wind: speed = still + wind
(x+w) * 3 = 1680 ...a
against wind: speed = still - wind
(x-w) * 4 = 1680 ...b
b-a ... 4x-4w-3x-3w = 0
x-7w = 0
x = 7w
substitution: (7w+w)*3 = 1680 8w = 560 wind speed (w) = 70
still speed (x) = 7w = 490 mile/hour
Answer:
-4m^5n on egde
Step-by-step explanation:
Answer:
the second option is correct, the one that you picked
Step-by-step explanation:
3x² - 2x + 7 = 0.
Using method of completing the square.
3x² - 2x = 0 - 7
3x² - 2x = -7 Divide through by 3.
x² - 2/3x = -7/3 ...........(d)
Coefficient of x = -2/3, half of it = 1/2*-2/3 = -1/3 square of it = (-1/3)² = 1/9
We add (1/9) to both sides of equation (d)
<span>x² - 2/3x = -7/3
</span>
<span>x² - 2/3x + 1/9 = -7/3 + 1/9
We factorize it by making using of half of the coefficient, -1/3
</span>
(x - 1/3)² = -7/3 + 1/9
<span>(x - 1/3)² = -20/9
</span>
That's the answer as asked by the question. -20/9
Answer:
Assuming you meant 25% of her money, the answer should be D - $29
Step-by-step explanation:
$29 * .25 = $7.25
$29 - $7.25 = $21.75
