changing the subject (maths)

[christy053]

can anyone help me figure out these changing the suject math problems ? Make x the subject of the following t=x+8
3x=z
x over 5 =t
c=x-7b
ta xxx

[gen2]

This looks suspiciously like homework to me so I'll just give you an example to follow.

(2x)/a + 8 = y

Subtract 8 from each side to leave the term with x in on the left

(2x)/a = y - 8

Multiply both sides by a to get rid of the denominator on the left

2x = a(y - 8)

Now divide both sides by 2 to leave x on its own on the left.

x = (a(y - 8))/2

or

x = ay/2 - 4a

[burnhal]

damn right! do your own homework!!

[christy053]

its not homework actually it is called revision and i needed to no how to work them out to do the revision ACTUALLYX

[burnhal]

in that case- all you have to remember is that what you do to one side of an equation must be done to the other side.
First one- take 8 away from each side
t-8 = x or x= t-8

second one divide both sides by 3
x = z/3

and so on

[snoozy]

Goodluck, hope the exam goes well for you.

Snoozy