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(5n2 – 4nm - 9m²) + (7n2 + 4nm +8m²) =

User Alfreema
by
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1 Answer

2 votes

Answer:


\left(5n^2-4nm-9m^2\right)+\left(7n^2+4nm+8m^2\right)=12n^2-m^2

Explanation:

Given the expression


\left(5n^2\:-\:4nm\:-\:9m^2\right)\:+\:\left(7n^2\:+\:4nm\:+8m^2\right)

Remove parentheses: (a) = a


=5n^2-4nm-9m^2+7n^2+4nm+8m^2

Group like terms


=5n^2+7n^2-4nm+4nm-9m^2+8m^2

Add similar elements:
5n^2+7n^2=12n^2


=12n^2-4nm+4nm-9m^2+8m^2

Add similar elements:
-4nm+4nm=0


=12n^2-9m^2+8m^2

Add similar elements:
-9m^2+8m^2=-m^2


=12n^2-m^2

Therefore, we conclude that:


\left(5n^2-4nm-9m^2\right)+\left(7n^2+4nm+8m^2\right)=12n^2-m^2

User Mark Bertenshaw
by
8.2k points

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