Can someone please help me with this which of these quadratic equations has exactly two solutions or zeros
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The mean of a set of data is -3.82 and its standard deviation is 2.31. find the z score for a value of 3.99.

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)