A function has the rule "multiply by two, and then subtract three." What is the output when the input is 8?

ten

thirteen

eighteen

twenty-two

Question

A function has the rule "multiply by two, and then subtract three." What is the output when the input is 8?

 ten

 thirteen

 eighteen

 twenty-two

calculusxy · Answer

$$f(x)=2x - 3$$

calculusxy · Answer

if you hence input 8 to where x is:
$$f(8) = 2(8) - 3$$

calculusxy · Answer

so now you can compute 2(8) - 3.

calculusxy · Answer

do you understand this?

anonymous · Answer

i really dont this kinda questions confuse me

anonymous · Answer

wait do i distibute the 2 then subtract the 3

calculusxy · Answer

no. the parenthesis is another way to show multiplication. but it means the same thing as:
$$2 \times 8 - 3$$

but what i did was replace the x to 8, to get the y (output), which is basically the answer to the expression

anonymous · Answer

thats what i meant distribute the 2 to the 8 then subtract so the answer would be 13

calculusxy · Answer

okay. sorry for misunderstanding what you said. but anyways, your answer is correct

anonymous · Answer

thank you for your help :)

calculusxy · Answer

no problem