f ( x ) = 4 x + b For the linear function f , b is a constant and

Question

f ( x ) = 4 x + b For the linear function f , b is a constant and f ( 7 ) = 28 . What is the value of b ?

Accepted Answer

Choice A is correct. For the linear function f , it&rsquo;s given that f 7 = 28 . Substituting 7 for x and 28 for f x in the given function yields 28 = 4 7 + b , or 28 = 28 + b . Subtracting 28 from each side of this equation yields 0 = b . Therefore, the value of b is 0 . Choice B is incorrect. Substituting 1 for b in the given function yields f x = 4 x + 1 . For this function, when the value of x is 7 , the value of f x is 29 , not 28 . Choice C is incorrect. Substituting 4 for b in the given function yields f x = 4 x + 4 . For this function, when the value of x is 7 , the value of f x is 32 , not 28 . Choice D is incorrect. Substituting 7 for b in the given function yields f x = 4 x + 7 . For this function, when the value of x is 7 , the value of f x is 35 , not 28 .

Question f-x-4-