The mistake is in step 3:
I: −2m =−12 − 2n
II: 2m = 8 + 8n
the student set both right sides of the equations equal (−12 − 2n = 8 + 8n), but the left sides aren't equal: first equation has -2m, second has +2m so the signs of one of the equations must be inverted first
Answer:
21 Students
Step-by-step explanation:
140 x .15 = 21
Answer:
1) 9x-4
Step-by-step explanation:
7x+2x= 9x
-8+4= -4
9x-4
Answer:
12
Step-by-step explanation:
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