Question

Solve the linear systems that abides by the following rules. Show all steps.

I. The first nonzero coefficient in each equation is one.

II. If an unknown is the first unknown with a nonzero coefficient in some equation, then that unknown doesn't appear in other equations.

II. The first unknown to appear in any equation has a larger subscript than the first unknown in any preceding equation.

a. x1 + 2x2 - 3x3 + x4 = 1.

-x1 - x2 + 4x3 - x4 = 6.

-2x1 - 4x2 + 7x3 - x4 = 1

b. x1 + 3x2 + x3 + x4 = 3

2x1 - 2x2 + x3 + 2x4 = 8

x1 - 5x2 + x4 = 5

c. x1 + 2x2 - 3x3 + 4x4 = 2

2x1 + 5x2 - 2x3 + x4 = 1

5x1 + 12x2 - 7x3 + 6x4 =3

it may seem a little confusing because i couldnt figure out how to write subscripts but for example 5x1 is 5x with subscript 1, and so on, none of the numbers immediately after the x variable are exponents they're all subscripts. If its confusing please let me know by commentiing! Thank you so much!  

Answer 1

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