Solve (m-n)(-n-m)

$$( m - n ) ( - n - m )$$

Evaluate

$$n^{2}-m^{2}$$

Solution Steps

Apply the distributive property by multiplying each term of m-n by each term of -n-m.

$$m\left(-n\right)-m^{2}-n\left(-n\right)+nm$$

Multiply -1 and -1 to get 1.

$$m\left(-n\right)-m^{2}+nn+nm$$

Multiply n and n to get n^{2}.

$$m\left(-n\right)-m^{2}+n^{2}+nm$$

Combine m\left(-1\right)n and nm to get 0.

$$-m^{2}+n^{2}$$

Expand

$$n^{2}-m^{2}$$

Solution Steps

Apply the distributive property by multiplying each term of m-n by each term of -n-m.

$$m\left(-n\right)-m^{2}-n\left(-n\right)+nm$$

Multiply -1 and -1 to get 1.

$$m\left(-n\right)-m^{2}+nn+nm$$

Multiply n and n to get n^{2}.

$$m\left(-n\right)-m^{2}+n^{2}+nm$$

Combine m\left(-1\right)n and nm to get 0.

$$-m^{2}+n^{2}$$