List of top Mathematics Questions on graphical solution of linear inequalities in two variables

Number of ways 3 boys and 4 girls can be arranged such that there is one girl between any 2 boys and one boy between any 2 girls.
For the system of linear equations  
2x+4y+2az=b
x+2y+3z=4 
2x-5y+2z=8 
which of the following is NOT correct ?  

If the system of linear equations

2x + y – z = 7

x – 3y + 2z = 1

x + 4y + δz = k, where δ, k ∈ R

has infinitely many solutions, then δ + k is equal to:

The shaded figure given below is the solution set for the linear inequations. Choose the correct option.
Consider $\frac{x}{2}+\frac{y}{4} \ge1,$ and $\frac{x}{3}+\frac{y}{4} \le1, x, y \ge0.$ Then number of possible solutions are :
The real values of $x$ and $y$ for which the following equality hold, are respectively $(x^{4}+2xi)-(3x^{2}+iy)=(3-5i)+(1+2iy)$
The inequalities $ {5x + 4y \geq 20, x \leq 6, y \leq 4}$ forms