(3x³ + 2x² - 5x) - (8x³ - 2x²<span>) =
</span>3x³ + 2x² - 5x - 8x³ + 2x² =
-5x³ + 4x² - 5x
Algebra gets much more complicated than that simple equation. This leaves many students WONDERing when, if ever, they’ll use algebra in real life. Does it have any use? If not, why do you have to learn it?
For starters, algebra is foundational for other classes. That means you’ll apply what you learn in algebra throughout school. Learning algebra helps to develop your critical thinking skills. That includes problem solving, logic, patterns, and reasoning. You need to know algebra for many professions, especially those in science and math. Not planning to go into those fields? You’ll probably still use algebra without even realizing it!
Consider these examples: It’s time to fill up your car’s gas tank. The price of gas per gallon is $3 and you only have $25 to spend. How much gas can you purchase? This can be answered by the algebraic equation, “3x = 25.” You must divide each side of the equation by 3 in order to isolate x. In this equation, x is equal to 25 divided by 3, which is 8.33 gallons of gas. If you need 10 gallons of gas, how much money do you need? When you solve that equation, you have algebra to thank!
There are many other examples of real-world uses of algebra, from comparing prices on similar products in a grocery store to figuring out what time you need to leave your house in order to meet a friend across town on time. If you ever WONDER why you need to learn something like algebra, don’t be afraid to ask your teacher or parent (or Wonderopolis!). Odds are, there’s a good reason!
Answer:
0-0=0
(You didn't attach anyting)
Step-by-step explanation:
Answer:
B. 16 hrs
Step-by-step explanation:
Distance = rate × time
The best way to do this is to make a table with the info. We are concerned with the trip There and the Return trip. Set it up accordingly:
d = r × t
There
Return
The train made a trip from A to B and then back to A again, so the distances are both the same. We don't know what the distance is, but it doesn't matter. Just go with it for now. It'll be important later.
d = r × t
There d
Return d
We are also told the rates. There is 70 km/hr and return is 80 km/hr
d = r × t
There d = 70
Return d = 80
All that's left is the time column now. We don't know how long it took to get there or back, but if it took 2 hours longer to get There than on the Return, the Return trip took t and the There trip took t + 2:
d = r × t
There d = 70 × t+2
Return d = 80 × t
The distances, remember, are the same for both trips, so that means that by the transitive property of equality, their equations can be set equal to each other:
70(t + 2) = 80t
70t + 140 = 80t
140 = 10t
14 = t
That t represents the Return trip's time. Add 2 hours to it since the There trip's time is t+2. So 14 + 2 = 16.
B. 16 hours
You add 6% sales tax (4000*.06 = 240) 4000+240 = 4240 So A. is your answer.
