Let <em>a</em> denote the airplane's speed in still air, and <em>w</em> the windspeed.
When the plane flies against the wind, it can travel an average speed of
(4500 km) / (6 h) = 750 km/h
so that
<em>a</em> - <em>w</em> = 750 km/h
Flying with the wind, it moves at a speed of
(2910 km) / (3 h) = 970 km/h
so that
<em>a</em> + <em>w</em> = 970 km/h
Add the two equations to eliminate <em>w</em> and solve for <em>a</em> :
(<em>a</em> - <em>w</em>) + (<em>a</em> + <em>w</em>) = 750 km/h + 970 km/h
2<em>a</em> = 1720 km/h
<em>a</em> = 860 km/h
Subtract them to eliminate <em>a</em> and solve for <em>w</em> :
(<em>a</em> - <em>w</em>) - (<em>a</em> + <em>w</em>) = 750 km/h - 970 km/h
-2<em>w</em> = -220 km/h
<em>w</em> = 110 km/h
Answer: x= 1/2
4x+8=10 1. Subtract 8 from both sides
-8 -8
——————
4x=2 2. Divide each side by 4
/4 /4
—————— 3. Simplify fraction
x=1/2
Answer:
400 meters
Step-by-step explanation:
Answer: 20
Step-by-step explanation:
Let 's complete our quadrilateral to a rectangle ; and subtract from it the area highlighted in red
Answer:
1) 2m + 3m2 - 4m=7
7) 3m2 – 2m + 4m= 11
8) 20 + 109 + 39 - 4= 164
3) 2m + 4m - 3m2= -3
9) 4xy + x + 2xy= 0
4) 2y + 14x - 7x + 9y= 18
10) 6m2 - 6m - 9m2= -51
Step-by-step explanation:
