in 3 variables, please. I'm tearing my hair out!! 3x^2+4y+z=7 2y+z=3 -5x^2+3y+8z=-31 Sorry to be such a pest, but math isn't my best subject.
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Originally Posted by JoanneMac in 3 variables, please. I'm tearing my hair out!! 3x^2+4y+z=7 2y+z=3 -5x^2+3y+8z=-31 Sorry to be such a pest, but math isn't my best subject. Hello Joanne, Tearing your hair out will not help. (1) (2) (3) Use (1) and (3) to eliminate x ---------------------------------- (4) Solve (2) for z and substitute in (4) (2) (4) Substitute y=5 into (2) to find z Substitute y=5 and z=-7 into (1) (1)
Hello, JoanneMac! I must assume that complex roots are expected. From [2], we have: . Add: . Substitute into [4]: . Substitute into [2]: .
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