Which function is the inverse of f(x) = 2x + 3?
f-1 (x)=-1/2x-3/2
f-1 (x)=1/2x-3/2
f-1 (x)=-2x+3
f-1 (x)=2x+3

f⁻¹(x) = ¹/₂ x - ³/₂

Option 1

Let

Rewrite and set the function with subject x.

Both sides are subtracted by 3.

y - 3 = 2x + 3 - 3

y - 3 = 2x

2x = y - 3

Both sides are divided by 2.

Let's replace and .

Thus, the inverse of f(x) = 2x + 3 is  

Option 2

Note:

Keywords: the inverse of function, f(x) = 2x + 3, one-to-one, onto, domain, range, interchange

step-by-step explanation:

well if you round, things become much more simple. round 5.95 to 6, 4.25 to 4, and 1.05 to 1. now, add 6+4+1 and that would equal 11. so the items together would equal to about $11.

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.