Using PADMAS really works
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
First expand the equation.
-5e+5+6e = -17
Next, combine the like terms.
e+5 = -17
e = -22
Answer:
= 25
Step-by-step explanation:
2 (-3)^2 - (4(-2) + 1)
2 (9) - (-8 + 1)
18 - (-7)
25
Answer:
b) 50
Step-by-step explanation:
750/15 = 50
