Extra credit?

Question

JIm paid $5.55 for 1 notepad and 7 pencils. Anne paid $12.28 for 3 notepads and 2 pencils. HOw much does each notebad cost?

Answer 1

notepads= n
pencil= p

(jim bought 1 notepad and 7 pencils so the equation would be n+7p=5.55. then you solve for n so it'll equal n=5.55-7p. see belowww)

n+7p=5.55
-7p  -7p
n=5.55-7p

(then anne bought 3 notepads and 2 pencils so the equation would be 3n+2p=12.28. so since you figured out that n=5.55-7p, you substitute that for the n in the anne's equation. see belowwww)

3n+2p=12.28
3(5.55-7p)+2p=12.28

(now you solve it)

3(5.55-7p)+2p=12.28
16.65-21p+2p=12.28
16.65-19p=12.28
-19p=-4.27
p=0.23

(so now you know the price of the pencils. remember when you solved that n=5.55-7p? well now you have to substitute 0.23 in for p. see below)

n=5.55-7p
n=5.55-7(0.23)
n=5.55-1.61
n=3.94

and now you know that each notepad equals 3.94 :)

hoped i helped!