Simple Equation confusion

• Feb 1st 2011, 11:28 AM
johnnerz
Simple Equation confusion
Hey guys;

I'm new to the forum so hello from me. I'm currently practicing simple linear-equations and feel comfortable with one and two-step equations.

However I've come across a slight obstacle with equations represented as thus;

17-y
_____ = 4.5
3

With this equation do I turn the denominator (3) across to 4.5 x (3) to make 13.5.

17-y = 13.5

The next step is where i become confused. I google-answered this example and the steps are;

17-y = 13.5
-y = -3.5
y= 3.5

How do i get 3.5? I've tried dividing 13.5 into 17 which is obviously wrong. Would be very grateful if someone could explain this to me.

thanks
J
• Feb 1st 2011, 11:31 AM
dwsmith
Quote:

Originally Posted by johnnerz
Hey guys;

I'm new to the forum so hello from me. I'm currently practicing simple linear-equations and feel comfortable with one and two-step equations.

However I've come across a slight obstacle with equations represented as thus;

17-y
_____ = 4.5
3

With this equation do I turn the denominator (3) across to 4.5 x (3) to make 13.5.

17-y = 13.5

The next step is where i become confused. I google-answered this example and the steps are;

17-y = 13.5
-y = -3.5
y= 3.5

How do i get 3.5? I've tried dividing 13.5 into 17 which is obviously wrong. Would be very grateful if someone could explain this to me.

thanks
J

13.5-17 = -3.5

-1 * -3.5 = 3.5

-1 * -y = y

y = 3.5
• Feb 1st 2011, 11:37 AM
johnnerz
thanks DW

Would i be correct then for this second example?

12-y
____ = 5
3

5*3 = 15
15-12 = 3
-y = 3
y= - 3
• Feb 1st 2011, 11:38 AM
dwsmith
Quote:

Originally Posted by johnnerz
thanks DW

Would i be correct then for this second example?

12-y
____ = 5
3

5*3 = 15
15-12 = 3
-y = 3
y= - 3

Correct.
• Feb 1st 2011, 11:40 AM
johnnerz
awesome, thanks for your help, I really appreciate it