Answer:
1. A, 450 = 2(p+w); 450 = 3(p-w)
2. A, 2 units
3. D, Between step 6 and step 7
Step-by-step explanation:
1. This one is confusing on first glance.
[tex]450 = 2(p+w); 450 = 3(p-w)[/tex] Lets break down this equation.
[tex]2(p+w)[/tex] means, the plane speed, plus the windspeed, will take 2 hours to travel 450 KM. The reason we add the plane speed and the windspeed is because we have a tailwind instead of a headwind, the wind is pushing us forward, adding to the planes speed.
[tex]3(p-w)[/tex] means, the plane speed, minus the windspeed, will take 3 hours to travel 450 KM. We subtract the wind speed from the plan speed because the wind is a headwind, it's pushing us backwards, taking away from the planes speed.
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2. Let set these up as two-sided equations.
[tex](6x+3) + (4x) + (2x + 1) = (5x) + (5x) + (3x+2)[/tex]
Combine like terms
[tex]12x + 4 = 13x + 2[/tex]
Subtract 12x from both sides
[tex]4 = 1x + 2[/tex]
Subtract 2 from both sides
2 = 1x, or x = 2.
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3. Take a look at step 6. You want to get x by itself, to do that, and get rid of the 8, you'd divide both sides by 8 to get [tex]x = -\frac{15}{4}[/tex]
