Find the value of k for which each of the following systems of linear equations has an infinite number of solutions:
2x + 3y = 7,
(k - 1)x + (k + 2)y = 3k.
Given: 2x + 3y = 7 – eq 1
(k - 1)x + (k + 2)y = 3k – eq 2
Here,
a1 = 2, b1 = 3, c1 = 7
a2 = k - 1, b2 = k + 2, c2 = 3k
Given that system of equations has infinitely many solution
∴ =
=
=
=
Here,
=
2×(k + 2) = 3×(k - 1)
2k + 4 = 3k – 3
3k – 2k = 4 + 3
K = 7
∴ k = 7