Why not + the 2xT?

[Murten]

Hey,

I’m gonna fire away a stupid question just so I understand it myself.

When we wanna figure out the amount of time it would be able to fly and do the :
0 = 100 - (2xT)

My first instinct was to + the paranthesis and then divide by two. I get the approach we did in the lecture but could I just get an explanation to why this would not work!

2xT = 100;
T = 50;

All the best

Martin

[garypettie]

Hi Murten,
When it comes to algebraic manipulation there’s usually more than one way that you can approach a problem.

One reason I solved the equation the way I did in the lecture was to try and keep it simple to follow - we’re always keeping ‘t’ on the right-hand side.
It also helped show a number of common techniques that we can use to chip away at everything surrounding the variable we’re interested in.

You could indeed do the following instead:
0 = 100 - (2 * t)
0 = 100 - 2t
2t = 100
t = 100/2
t = 50

Regardless of which approach you take, you should always be able to verify that you got the correct answer by substituting it back into the original equation.
In this case:
0 = 100 - (2 * 50)
0 = 100 - 100
0 = 0

[Murten]

Hey,

Thanks for a great answer. Sometimes I need to have it explained / confirmed to wrap my head around stuff:)

I hope you do not work too much this weekend!

//M