Re-arranging formula rules

[liz]

Hi,

I am just wondering why 9/5C - C = -32 becomes C(9/5-1) = -32 in the problem below? What is the rule that makes this so?

 

[Deleted member 4993]

Hi,

I am just wondering why 9/5C - C = -32 becomes C(9/5-1) = -32 in the problem below? What is the rule that makes this so?

View attachment 3964

Do you understand that:

a*(x + y) = a*x + a*y → this is called distributive property of multiplication.

The operation you refer to is in the "reverse direction" [ a*x + a*y = a * (x + y)].

It is also sometimes referred to as factorization (in your problem - recognizing common factor "c" and factoring it out).