Question

Stackable polystyrene cups have a height h1=13 cm.

Two stacked cups have a height of h2=16 cm.
Three stacked cups have a height of h3=19 cm.
Find the equation for hx=



Your friend is 185cm tall.
Find out how many cups you will need to reach the height of your friend. cups=

Answer 1

First identify the difference in height when you add each cup

Answer 2

3cm

Answer 3

@jaeuni

Answer 4

sorry have to recalculate something

Answer 5

ok back

Answer 6

So you know, based on the problem, that there will be a fixed number in this equation, regardless of how many cups you have....do you know what it is?

Answer 7

*hint* you know that the height will be at least this "fixed number" as long as you have 1 cup

Answer 8

@vzforever

Answer 9

ok

Answer 10

@jaeuni is it 3?

Answer 11

3 or 13? is the equation 3x+13?

Answer 12

Maybe "fixed number" was the incorrect way to put it...let me just tell you and explain to you why

So as long as you have 1 cup, you know that the height will be at least 13 cm (because that's the height of 1 cup)

Answer 13

you're close with the equation

Answer 14

But if you use that equation, you'll see that at x= 1 cup, you have a height of 16 and that's not correct

Answer 15

so is it 3x+10?

Answer 16

If you plug in a number for x, does that give you the correct height?

Answer 17

yes

Answer 18

Your friend is 185cm tall.
Find out how many cups you will need to reach the height of your friend. cups=

Answer 19

When writing out equations, you want to make them as similar to how the problem is worded. Since there is no "10" provided by the problem, I wouldn't say that's the right equation (even if it yields the right numbers)