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.
+3454 1.) Matt's answer is incorrect. This question is dealing with the order of operations, and from −10 + 30 ÷ 5
to 20 ÷ 5 he went out of the order of operations, doing addition before division.
Karen's answer is also incorrect. In step 6 – 4( –2)2 + 30 ÷ 5 to 6 – 4( −4) + 30 ÷ 5, her exponets are wrong. When she did (-2)2 she got -4 instead of +4.
+3454 1.) Matt's answer is incorrect. This question is dealing with the order of operations, and from −10 + 30 ÷ 5
to 20 ÷ 5 he went out of the order of operations, doing addition before division.
Karen's answer is also incorrect. In step 6 – 4( –2)2 + 30 ÷ 5 to 6 – 4( −4) + 30 ÷ 5, her exponets are wrong. When she did (-2)2 she got -4 instead of +4.
+3454 2.) A possible algebraic equation expression for these phone plans would be c = mr + a.
c = total cost after m months
m = number of months
r = monthly rate
a = activation fee
This would be an algebraic equation for the cell phone plans because they would tell you the total cost for both of the plans after a given amount of years and with differing activation fees and monthly charges.
If you think about it, this is the same equation as y=mx + b, but with different letters for unknowns! Thus, you could graph the two cell phone plans if you knew their montly rates and activation fees, and it would show you which plan would be better depending on how many years you are planning to have that plan, aswell as the point that it wouldn't matter what plan you bought, because it would cost you the same. (where the lines intercect)
