Thread: combining formulae so that part of the equation is removed.

Hi I'm studying forensics and i need help understanding how to work these out.I know how to rearrange formulae I'm just having trouble applying it to these type of equations. Help would be very much appreciated

The question states that I must combine the formulae so that I remove the letter in bold from the resulting equation.

6-2q=r and T=3qrs

here is what i've done so far

T=3qrs . i divide the r


t/r=3qs then I multiply the t

r=3qst this allows me to combine it with the first equation

6-2q=3qst

the problem that i now have is how to arrange this formulae as the question stated.
to remove the q this is where I'm at a loss and my attempts have failed

if I be could showed the method it would be great.

thanks

reefcake

Originally Posted by reefcake

Hi I'm studying forensics and i need help understanding how to work these out.I know how to rearrange formulae I'm just having trouble applying it to these type of equations. Help would be very much appreciated

The question states that I must combine the formulae so that I remove the letter in bold from the resulting equation.

6-2q=r and T=3qrs

here is what i've done so far

T=3qrs . i divide the r


t/r=3qs then I multiply the t

r=3qst this allows me to combine it with the first equation

6-2q=3qst

the problem that i now have is how to arrange this formulae as the question stated.
to remove the q this is where I'm at a loss and my attempts have failed

if I be could showed the method it would be great.

thanks

reefcake

Welcome to MHF.

Solve one of the equations for q. The following one may be easiest.INDENT]T=3qrs[/INDENT]

Then take whatever it is that you find q is equal to, and substitute that for q in the other equation

6-2(whatever q is equal to)=r

Originally Posted by SammyS

Welcome to MHF.

Solve one of the equations for q. The following one may be easiest.INDENT]T=3qrs[/INDENT]Then take whatever it is that you find q is equal to, and substitute that for q in the other equation

6-2(whatever q is equal to)=r

Hi thanks for your response and greeting

i attempted it again, tho my algebra is somewhat rusty heres what I got:

T=3qrs , t/q=3rs, q=3rst. here im unsure if can move the q without the 3

tho if can move q freely it combined would be:

6-2x3rst=r ? though I not to sure as I don't know what to do with numbers

thanks

Originally Posted by reefcake

Hi thanks for your response and greeting

i attempted it again, tho my algebra is somewhat rusty here's what I got:

T=3qrs , t/q=3rs, q=3rst. here I'm unsure if can move the q without the 3

No. Divide both sides by 3rs.

tho if can move q freely it combined would be:

6-2x3rst ? though I seem to be unsure on what do to with numbers

as I'm sure I've probably made an basic error.

thanks

Originally Posted by SammyS

No. Divide both sides by 3rs.

so (t/q)/3rs, q=t/3rs? which would give you 6-2(t/3rs)=r

ta

Correct !

Originally Posted by SammyS

Correct !

yayyyyyyyy!!!!!!!!!!!

thank you for your help it is much appreciated