sat suite question viewer

Algebra / Linear functions Difficulty: Medium

If f(x)=x+7 and g(x)=7x, what is the value of 4f(2)g(2)?

Back question 60 of 152 Next

Explanation

Choice C is correct. The value of f(2) can be found by substituting 2 for x in the given equation fx=x+7, which yields f2=2+7, or f2=9. The value of g2 can be found by substituting 2 for x in the given equation gx=7x, which yields g2=72, or g2=14. The value of the expression 4f2-g2 can be found by substituting the corresponding values into the expression, which gives 4(9)14. This expression is equivalent to 36-14, or 22 .

Choice A is incorrect. This is the value of f2-g2, not 4f2-g2.

Choice B is incorrect and may result from calculating 4f2 as 4(2)+7, rather than
4(2+7).

Choice D is incorrect and may result from conceptual or calculation errors.