Question

Identify which property of equality is used to transform Equation 1 to Equation 2.



Equation 1: 3x = 12
Equation 2: x = 4



A.
addition property of equality


B.
subtraction property of equality


C.
multiplication property of equality


D.
division property of equality

Answer 1

Okay so if you just look at the x's for now, what do you have to do to 3x to get x?
(ie how do you get from 3 to 1? Remember that it is 3*x and 1*x)

Answer 2

i think it is c

Answer 3

If you were going from Equation 2 to Equation 1, then it would be C, because you would be making it in essence, 3 times bigger

Answer 4

ok

Answer 5

it is d

Answer 6

why is it d?
(That is correct! But I want to make sure you understand why :) )

Answer 7

because 3/4=12

Answer 8

i don't really know

Answer 9

Right so to get from 3x to x, you have to divide by 3, okay?
And to get from 12 to 4, you again have to divide by 3

So if you have to divide by 3 on both sides of the equation to get from one to the other, then it is a division property of equality.

So for example:
Equation 1: 2x=4
Equation 2: x=2

You have to divide by 2 to go from equation 1 to equation 2?

Does that make sense? If not, let me know.

Answer 10

actually i do know why but i can't explain it

Answer 11

oh i get it now!

Answer 12

Good :)