I think you answer should be 51
YES
We can work out the inverse using Algebra. Put "y" for "f(x)" and solve for x:
<span><span>The function: f(x)=2x+3
</span><span>Put "y" for "f(x)": y=2x+3
</span><span>Subtract 3 from both sides:
y-3=2x
</span><span>Divide both sides by 2:
(y-3)/2=x
</span><span>Swap sides: x=(y-3)/2</span><span>
</span><span><span>Solution (put "f-1(y)" for "x") :</span> <span>f-1(y)</span>=(y-3)/2</span></span>
Answer: 76
Step-by-step explanation:
The best option is to buy 2 gallons for $5.98 because if you do your work and check how much everything else costs for 2 gallons (example: 1/4 gallons multiplied by 8 equals $14.40 which is 2 gallons) you'll see that everything else is too expensive, and the 2 gallons for $5.98 is the best answer.
I hope this helps :)