Answer:
28
Step-by-step explanation:
For Luis to get a mean of 20 he would need:
14 + 18 + 15 + 25 + x (unknown number of goal he needs) / 5 = 20
Therefore 14 + 18 + 15 + 25 + x = 100
Solve for x to get 28
Here,
f(x) = 7
x = ?
Now,
f(x) = x^2 - 2
or, 7 = x^2 - 2
or, 7 + 2 = x^2
or, x^2 = 9
◆ x = 3
a) 3
I hope it's help you...
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