Answer:
g(x) = 10(x +1)² +5
Explanation:
When a point is translated 3 units down, its y-value is 3 less than it was. The graph of f(x) is translated 3 units down by subtracting 3 from the value of f(x).
g(x) = f(x) -3 . . . . . translates f(x) 3 units down
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For f(x) = 10(x +1)² +8, we want ...
g(x) = f(x) -3 = (10(x +1)² +8) -3
g(x) = 10(x +1)² +5