# The function f is defined by f(x) =…

# Solution:

We are given the function defined by f(x) = √x – 10, and we also see that f(t) = u. First, let’s determine what f(t) looks like and then set the result equal to u.

f(t) = √t – 10

√t – 10 = u

To finish, we need to get t in terms of u.

√t = u + 10

t = (u + 10)^2

**Answer: D**

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Scott Woodbury-Stewart is the founder & CEO of Target Test Prep. A passionate teacher who is deeply invested in the success of his students, Scott began his career teaching physics, chemistry, math, and biology. Since then, he has spent more than a decade helping students gain entry into the world’s top business schools, logging 10,000+ hours of GMAT instruction. Scott also served as lead content developer and curriculum architect for the revolutionary quant course Target Test Prep GMAT Quant.