Linear Equation Solver Specification
Task: Solving Two Equations in Two Unknowns
Write a menu driven program to solve systems of 2 linear equations in 2
unknowns. The equations are of the form:
a * x + a * x = c
(1,1) 1 (1,2) 2 1
a * x + a * x = c
(2,1) 1 (2,2) 2 2
Where the a's and c's are the coefficients and righthandsides
to be input, and x1 and x2 are the unknowns to be determined by the program.
The menu should allow the following commands:

(G)et Equations:

The user should be prompted to enter the coefficients and righthandsides
for the two equations.

(D)isplay Equations:

The equations should be displayed in a nice readable form.

(S)olve Equations:

The equations should be solved for the unknowns, x1 and x2.

(P)rint Solution:

The solutions should be displayed in a nice readable form.

(V)verify Solution:

The solutions should be plugged into the equations and verified
that the lefthandside equals the righthadside to within
some predetermined margin of error.

(N)ew Error:

The user should be prompted to enter a new value for
the error margin. If none is entered, the default 0.00001 should be used.

(H)elp:

Print a list of commands available and a brief description of each.

(Q)uit:

Terminate the program.
We should make this program as "robust" as possible; i.e. we should be
able to tolerate user mistakes and take some corrective action.
Where do we
begin?