Final answer:
The system of equations formed by the three planes does not have a common solution, so the planes do not have a common point of intersection.
Step-by-step explanation:
To determine if the three planes have at least one common point of intersection, we need to solve the system of equations formed by the planes. The system of equations is:
x1 + 4x2 + 3x3 = 5
x2 - 3x3 = 1
3x1 + 15x2 = 12
We can solve this system using various methods such as substitution or elimination. Let's use the elimination method:
Multiply the second equation by 4 to make the coefficients of x1 and x2 the same as in the third equation. The system becomes:
x1 + 4x2 + 3x3 = 5
4x2 - 12x3 = 4
3x1 + 15x2 = 12
Now subtract the second equation from the first equation to eliminate x2. The system becomes:
x1 -_ 12x3 = 1
4x2 - 12x3 = 4
3x1 +__9x3 = 9
Now subtract the third equation multiplied by 3 from the second equation multiplied by 4 to eliminate x1. The system becomes:
x1 -_ 12x3 = 1
4x2 - 12x3 = 4
__9x3 - 9x3 = -15
Simplify the third equation to:
0 = -15
Since this equation is not true, it means that the system of equations does not have a solution. Therefore, the three planes do not have a common point of intersection.