Answer:
t=12
Step-by-step explanation:
Step 1: Subtract t from both sides.
−t+5−t=t−19−t
−2t+5=−19
Step 2: Subtract 5 from both sides.
−2t+5−5=−19−5
−2t=−24
Step 3: Divide both sides by -2.
−2t−2=−24−2
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
Inequalities require a sign of greater than, less than, greater than or equal to, or less than or equal to. It's never just a single number solution. It's always going to be a range of solutions
