Can someone help with making x the subject or changing the subject of a formula?

Question

Please help with making x the subject. I have the answers but they don't show working. Helpful links with ones like these will also help. Thanks.

x=(yz) / (y+z) (make y the subject)
L=4(root(a^2 + 4h^2) -a all / by 3
(L equals 4 times square root of a^2 + 4h^2 (end root) take a. all divided by 3) make h the subject.

Answer 1

x= yz/(y+z)



multiply both sides by (y+z):



x(y+z) = yz



xy +xz = yz



xz = yz -xy



xz = y(z-x)



divide both sides by (z-x)



xz/(z-x) = y



y= xz/(z-x)









l= 4(√(a^2+4h^2)) -a divided by 3



multiply both sides by 3



3l = 4(√(a^2+4h^2)) -a



3l +a = 4(√(a^2+4h^2))



divide both sides by 4



(3l+a)/4 = √(a^2+4h^2)



square both sides:



[(3l+a)/4]^2 = a^2 +4h^2



[(3l+a)/4]^2 -a^2 = 4h^2



divide both sides by 4



[[(3l+a)/4]^2 -a^2]/4 = h^2



square root both sides:



√[[[(3l+a)/4]^2 -a^2]/4]= h



h= √[[[(3l+a)/4]^2 -a^2]/4]





BUT it's also possible that you meant this:



l= 4(√(a^2+4h^2) -a) divided by 3



3l = 4(√(a^2+4h^2) -4a



3l +4a = 4(√(a^2+4h^2)



divide both sides by 4:



3l/4 +4a/4 = √(a^2+4h^2)



3l/4 +a = √(a^2+4h^2)



(3l/4 +a)^2 = a^2 +4h^2



(3l/4 +a)^2 -a^2 = 4h^2



[(3l/4 +a)^2 -a^2]/4 = h^2



√[[(3l/4 +a)^2 -a^2]/4] = h



h= √[[(3l/4 +a)^2 -a^2]/4]







As you can see, brackets make the difference, try to use them a little more efficiently!

Answer 2

well it's pretty hard to explain while typing, but the main rule is that whatever you do to one side of the equation, you must also do to the other. for example, to make x the subject of this equation:



y=x-2



I need to do the same to each side, and somehow be left with just x on one side. So I add two to each side, leaving me with this:

y+2=x-2+2

which I can simplify to make

y+2=x or x=y+2

Answer 3

Leave your ex alone. She's sick of the constant calls and texts. Move on.