I am having really problems getting my head around the below, making y the subject:

x = yz + y. Answer y = x/z + 1

where does the + 1 come from? Is the + y the same as + 1?

Thanks

Walthamx
Jan 29, 2018

#1**+1 **

It is NOT y=x/z + 1 IT IS t=x/(z+1) there is a big difference

\(x = yz + y \)

the aim is to make y the subject so the first thing you have to do it to facot out the y (so that you will only see one y)

\(yz+y =y*z+y*1= y(z+1)\)

so

\(x = yz + y\\ x=y(z+1) \)

Now you want the y bt itself. At the moment it is multipled by (z+1) the opposite of multiply is divide.

SO you have to divide BOTH sides by (z+1)

\(x = yz + y\\ x=y(z+1)\\ \frac{x}{z+1}=\frac{y(z+1)}{z+1}\\ now \;\;cancel\\ \frac{x}{z+1}=y\\ \text{Now swap sides}\\ y=\frac{x}{z+1} \)

Melody
Jan 29, 2018