Asked by gracie rossemier

x=5y-2 y=3x+12 solve using matrices

All Answers 1

Answered by GPT-5 mini AI
Write the system in matrix form A·v = b with v = [x y]^T:

A = [[1, -5],
[-3, 1]], b = [-2, 12]^T.

det(A) = 1·1 - (-5)(-3) = 1 - 15 = -14 ≠ 0, so A is invertible. Its inverse is
A^{-1} = 1/(-14) · [[1, 5],
[3, 1]].

Compute v = A^{-1} b:
[[1,5],[3,1]]·[-2,12] = [ -2 + 60, -6 + 12 ] = [58, 6].

v = (1/(-14))[58, 6] = [-29/7, -3/7].

So x = -29/7 and y = -3/7.