Answer:
A. Only Nombeko.
Explanation:
Solution to teacher's system of linear equations:
-3x + 12y = 15 ... (i)
7x - 10y = -2 ... (ii)
Multiplying (i) by 7 and (ii) by 3 we get;
-21x + 84y = 105 ... (i)
21x - 30y = -6 ... (ii)
Adding (i) and (ii) gives;
0x + 54y = 99
54y = 99
Dividing through by 9 gives;
6y = 11
So y = 11/6
Finding the value of x by substituting the y in (i) with 11/6;
-3x + 12(11/6) = 15
-3x + 22 = 15-3x = 15 - 22 = -7
-3x = -7
x = 7/3
Only Nombeko's system of linear equations has a solution of x=7/3 and y=11/6 .