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Pls help or explain steps ​

Pls help or explain steps ​-example-1

2 Answers

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Solving for a variable means to rewrite the equation so that the desired variable is alone on one side. So, we have to "move" all the other variables/constants in order to make this happen. We are allowed to add/subtract the same quantity from both sides, or to multiply/divide both sides by any non-zero number.

Let's start with the first example: we are given

11.
d=rt

the variable
r is not alone on the right hand side because it is multiplied by
t. We can reverse this by dividing both sides by
t: the equation becomes


(d)/(t)=(rt)/(t)=r

So, we have written the equation as
r=(d)/(t), which means that
r now sits alone on one side of the equation, and thus we have solved the equation for
r!

Similarly, we do all the others:

12.
f=v+at

Subtract
at from both sides to get


f-at=v

13.
Ax+By=C

Subtract
By from both sides to get


Ax=C-By

Now divide both sides by
A to get


x = (C-By)/(A)

14.
A=(1)/(2)Pl

Multiply both sides by 2:


2A=Pl

Divide both sides by
P:


(2A)/(P)=l

User Adam Holmberg
by
5.4k points
1 vote

Answer:

11. r = d/t

12. v = f - at

13. X = (C - BY)/A

14. l = 2A/P

Explanation:

* Lets explain how to solve this problems

11.

- The equation is d = rt

- We want to solve the equation for r, then we must separate r in

one side and the rest in the other side

∵ r is multiplied by t

∴ divide both sides by t

∴ d/t = r

- Switch the two sides

r = d/t

12.

- The equation is f = v + at

- To solve the equation for v, then we must separate v in

one side and the rest in the other side

∵ v is added to at

∴ subtract at from both sides

∴ f - at = v

- Switch the two sides

v = f - at

13.

- The equation is AX + BY = C

- To solve the equation for x, then we must separate x in

one side and the rest in the other side

∵ AX is added to BY

∴ subtract BY from both sides

∴ AX = C - BY

∵ X is multiplied by A

∴ Divide both sides by A

X = (C - BY)/A

14.

- The equation is A = 1/2 Pl

- To solve the equation for l, then we must separate l in

one side and the rest in the other side

∵ l is multiplied by 1/2 P

∴ Divide both sides by 1/2 P

∴ A/(1/2 P) = l

- A divided by 1/2 = 2A

∴ 2A/P = l

- Switch the two sides

l = 2A/P

User Nstehr
by
5.0k points