SOLUTION: Please help me solve this equation: {{{ z= sqrt( z^2 + 4z - 18 ) }}}

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Question 873146: Please help me solve this equation: +z=+sqrt%28+z%5E2+%2B+4z+-+18+%29+
Found 2 solutions by josgarithmetic, jim_thompson5910:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Square both sides. This example will be then a ... a linear equation in z, after a bit of simplifying.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
+z=+sqrt%28+z%5E2+%2B+4z+-+18+%29+


+z%5E2=+%28sqrt%28+z%5E2+%2B+4z+-+18+%29%29%5E2+ Square both sides (to undo the square root on the right side)


+z%5E2=+z%5E2+%2B+4z+-+18+


+z%5E2-z%5E2+=+4z+-+18+


+0+=+4z+-+18+


+4z+-+18+=+0+


+4z+=+18+


+z+=+18%2F4+


+z+=+9%2F2+


I'll let you check the answer.