Answer: -12
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Step-by-step explanation:
Let's simplify the 7+(-12) portion first
Draw a vertical number line. Plot a point at 7. Then move down 12 units to arrive at -5
Or you could start at -12 and move up 7 units to arrive at -5
This tells us that 7+(-12) = -5
So the overall 7+(-12)+(-7) turns into -5+(-7)
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Draw another vertical number line, or use the one already drawn in the previous section.
Plot a point at -5. Then move down 7 units to arrive at -12
Or start at -7 and move down 5 units to arrive at -12
Therefore, -5 + (-7) = 7+(-12)+(-7) = -12 is the final answer
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Shortcut:
The 7 and -7 in the original expression add to 0. They cancel each other out. So we're left with -12