+4 For certain values of k and m, the system
a+2b=-3
4a+2b=k-a-mb
has infinitely many solutions (a, b). What are k and m?
+1768 We get 3a + 2b = 2
6a + 2b = k - 3a - ab
Then we get 9a + (2 + m) * b = k
Equation first is equivalent to
9a + 6b = 6
There are an infinite number of solutions if second equation and third equation are equivalent. That is true only if the coefficients of b in both equations are the same and the constants in both are the same.
2+m = 6 --> m = 4
k = 6
ANSWERS: k = 6; m = 4
