Polynomials in the fourth degree are called quartic equations. In solving the roots of polynomials, there are techniques available. For quadratic equations, you use the quadratic formula. For cubic equations, you use the scientific calculator. But for quartic equations and higher, it is very complex. The method is very lengthy and can get very messy because you introduce a lot variables. So, I suggest you do the easiest method to estimate the roots.
Graph the equation by plotting arbitrary points. The graph looks like that in the figure. The points at which the curve passes the x-axis are the solution which are encircled in red.In approximation, the rational roots or zero's are -3.73, -1, -0.28 and 2.
The answer is 3.785, but rounding it to the nearest hundredth is 3.68 or 3.79, depending on rather they wanted you to take the t and round up or just leave it off.
Kx-3y=k y=4x+1 ( we will put it in 1st equation ) kx - 3 (4x+1)=k kx - 12 x - 3 =k kx - 12 x = k+3 x(k-12) = k+3 x= Also y= We can not divide with zero. k-12=0 k=12 For k= 12 equations have no solutions.