Answering a question like this is just a matter of plugging in and cranking out.
You are given an expression for x in terms of y, an expression for y in terms of
k, and the value of k.
Plug into the second equation to find y:
Now plug y = 10 into the first equation to find x:
x = y^2 = 10^2 = 100The answer is (E).
EXPONENTS—KEY OPERATIONS
You can’t be adept at algebra unless you’re completely at ease with
exponents. Here’s what you need to know.
Multiplying powers with the same base: To multiply powers with the same
base, keep the base and add the exponents:
x^3 × x^4 = x3+4 = x^7Dividing powers with the same base: To divide powers with the same base,
keep the base and subtract the exponents: