Question

Two of your friends, Matt and Karen, both run to you to settle a dispute. They were working on a math problem and got different answers. Wisely, you decide to look at their work to see if you can spot the source of confusion.
Matt
6 – 4(3 – 5)^2 + 30 ÷ 5
6 – 4(–2)^2 + 30 ÷ 5
6 – 4(4) + 30 ÷ 5
6 – 16 + 30 ÷ 5
−10 + 30 ÷ 5
20 ÷ 5
4
Karen
6 – 4(3 – 5)^2 + 30 ÷ 5
6 – 4(–2)^2 + 30 ÷ 5
6 – 4(−4) + 30 ÷ 5
6 + 16 + 30 ÷ 5
6 + 16 + 6
22 + 6
28
Explain to Matt and Karen who, if any, is correct and identify errors that you find.Provide correct manner

Answer 1

I suppose you should follow BEDMAS or PEMDAS for this question.

Answer 2

Try it out yourself and see who's correct, if either of them are. If that doesn't work, I can work through it with you.

Answer 3

I tried using PEMDAS but it wasn't giving me the answers they used. I haven't tried BEDMAS I've never used that form

Answer 4

Same thing, really. Just "brackets" instead of "parentheses" or whatever that P stands for, haha.

Answer 5

What was your answer? I worked it out myself, too.

Answer 6

Have you looked carefully at the two solutions given in the question? You can spot the difference in the second solution very easily.

In the first, there is a step where they didn't follow PEMDAS.

In the second, they applied an exponent incorrectly.

Answer 7

i'll look and try again, to see if I messed up somewhere

Answer 8

Your answer shouldn't match either of theirs. :) I worked it out to be -4, hby?

Answer 9

When I worked it out the first time before coming here I got -4

Answer 10

Then you were right. =D

Looking back at their solutions, Matt subtracted 16 from 6 before he divided.
Karen said (-2)^2 is -4, which it isn't--it's +4.

Answer 11

So both of them were incorrect?

Answer 12

Mhm, they're not nearly as brilliant as we are. :D

Answer 13

Yes, that is true! Hahaha, thank you so much for the help!

Answer 14

:D any time.