Answer:

Step-by-step explanation:

Two of the numbers were switched in a multiplication equation, so the answer would be commutative- multiplication.
Answer:

Step-by-step explanation:
To solve for q, we initially place everything with the term q to one side of the equality, and everything without the term q to the other side of the equality.
So


We find the square of both sides of the equation. So




Answer:
f= -15
Step-by-step explanation:
u just have to divide
-75/5= -15 so f equal -15
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