xy - 5 = k (move the known term to the right with changed sign)
xy = k + 5
Now we have x multiplied for y...to delete the y, divide both terms for y.
xy/y = (k+5)/y
x = (k+5)/y
3y + 5x = 7
Move 3y to the right with changed sign (this to make x the variable for which we solve the equation)
5x = 7 - 3y
Divide every term for 5
5x/5 = 7/5 - 3y/5
x = 7/5 - 3y/5
m/n = p-6
Multiply both terms for n, since we should delete the fraction m/n
m = pn-6n
Factor...
m = n(p-6)
to find n, move m to the right with changed sign.
Divide both for p-6
m/p-6 = n
n = m/p-6
F = 9c/5 + 32
9c/5 + 32 = F
Move 9c/5 to the left (don't change sign) to make it the default variable. And move all the rest to the right but changing sign.
9c/5 = f - 32
To delete the fraction, multiply every term for 5
9c = 5(f) + 32(5)
9c = 5f - 160
Divide both for 9
c = 5f/9 - 160/9