SOLUTION: a + b + c + d = 7 2a - b + c - 2d= -13 3a + b - 2c - d = 5 4a - b + 3c - d = -10

Algebra ->  Systems-of-equations -> SOLUTION: a + b + c + d = 7 2a - b + c - 2d= -13 3a + b - 2c - d = 5 4a - b + 3c - d = -10       Log On


   

Question 1124978: a + b + c + d = 7
2a - b + c - 2d= -13
3a + b - 2c - d = 5
4a - b + 3c - d = -10

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!


We have Ax = b and the solution we want is BAx=Bb where B is A%5E-1

Using your favorite matrix inverter website and/or computing by hand:
B =

So ==>


Check:
1+3+(-2)+5 = 7 (ok)
2(1)-3+(-2)-2(5) = -13 (ok)
3(1)+3-2(-2)-5 = 5 (ok)
4(1)-3+3(-2)-5 = -10 (ok)