Equation Solver

Given a subset of

x = 1.2
3*x+2*(1-x+(2*x)*0.5)-4=x+7
(1 - (1 - (1 - x*2))) = 9999.9
1 * 2 * 3 * 4 * x=195
(2 + 2*x)/2 = 3 * x
123 = 1000*x

Output the corresponding solution for each equation.