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3 years ago

Help help help help

Mathematics

2 answers:

slega [8]3 years ago

8 0

Answer:

n=4

Step-by-step explanation:

(7+1)+n=(4+7)+1

7+1+n=4+7+1 (subtract 7 from both sides)

1+n=4+1

1+n=5

n=5-1 (Subtract 1 from both sides)

n=4

olga nikolaevna [1]3 years ago

6 0

Answer:

n = 4

Step-by-step explanation:

Actually, in this problem, you can compare the numbers on the right to the numbers on the left and see that n must be 4 to make the lists match. (It's a problem in pattern matching.)

If you need to, you can rearrange the numbers:

(7 + 1) + n = (7 + 1) + 4

If that doesn't work for you, you can add up the numbers on each side and form the equation ...

8 + n = 12

In second-grade terms, this is ...

8 + ___ = 12

Hopefully, you are sufficiently familiar with your math facts to know that 4 will complete this math fact.

If that doesn't work for you, then invoke the addition property of equality and add -8 to both sides of the equation.

8 -8 +n = 12 -8

n = 4

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