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What is the value of z so that-9 and 9 are both solutions of x^2+z=103?

A) -22
B) 3
C) 22
D 184

User Gjergj
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1 Answer

3 votes
If the sol'ns are -9 and 9, then we can use this to form our eq'n:
(x - 9)(x + 9) = 0
x^2 - 81 = 0
so...
x^2 + z - 103 = x^2 -81
z - 103 = -81
z = -81 + 103
z = 22
User Nertila
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