TUESDAY MATH 8 WARM-UP

Find the error in the problem below
19 - 2k = 3k - 1
     +3k   +3k
19 + 1k = -1
-19           -19
k = -20

• They should have divided by 1 for the last step
• They should add 19 instead of subtracting 19
• I can not find an error
• Instead of adding 3k they should subtract 3k

Tags

CCSS.HSA.REI.A.1

Is the solution below correct?
5d = 2d - 18
-2d   -2d
3d = -18
d = 6

• Yes
• No

Tags

CCSS.7.EE.B.4A

Is the solution below correct?
-6z + 13 = 7z
+6z           +6z
13 = 13z
z = 1

• Yes
• No

Tags

CCSS.HSA.REI.A.1

Identify the error in the picture given.

• There is no error

• Subtracted 18 instead of adding 18

• Subtracted 5d instead of adding 5d

• Divided by -3 instead of multiplying by -3

Tags

CCSS.HSA.REI.A.1

Identify the error.

13 -6z = 7z

+6z +6z

13 = 13z

z = 1

• divided by 13 instead of multiplying by 13

• Added 6z instead of subtracting

• No error

• 7z + 6z does not equal 13z

Tags

CCSS.HSA.REI.A.1

5 + 2(n + 1) = 2n
Bill says the first step is to add and get
7(n + 1) = 2n

• Bill is correct
• Bill is wrong; he should have distributed the 2 first.
• Bill is wrong; he should have subtracted 5 from both sides first.
• Bill is wrong; he should have divided by 2 firat.

Tags

CCSS.8.EE.C.7B