Datrys 7m^2-5-[m^2+3n-(5-n)-(-3+m^2)]}-(2n+3)

$$7 m ^ { 2 } - 5 - [ m ^ { 2 } + 3 n - ( 5 - n ) - ( - 3 + m ^ { 2 } ) ] \} - ( 2 n + 3 )$$

Enrhifo

$$7m^{2}-4n-3$$

Camau Ateb

I ddod o hyd i wrthwyneb 5-n, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-\left(m^{2}+3n-5+n-\left(-3+m^{2}\right)\right)$$

Cyfuno 3n a n i gael 4n.

$$7m^{2}-5-\left(m^{2}+4n-5-\left(-3+m^{2}\right)\right)$$

I ddod o hyd i wrthwyneb -3+m^{2}, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-\left(m^{2}+4n-5+3-m^{2}\right)$$

Adio -5 a 3 i gael -2.

$$7m^{2}-5-\left(m^{2}+4n-2-m^{2}\right)$$

Cyfuno m^{2} a -m^{2} i gael 0.

$$7m^{2}-5-\left(4n-2\right)$$

I ddod o hyd i wrthwyneb 4n-2, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-4n+2$$

Adio -5 a 2 i gael -3.

$$7m^{2}-3-4n$$

Ehangu

$$7m^{2}-4n-3$$

Camau Ateb

I ddod o hyd i wrthwyneb 5-n, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-\left(m^{2}+3n-5+n-\left(-3+m^{2}\right)\right)$$

Cyfuno 3n a n i gael 4n.

$$7m^{2}-5-\left(m^{2}+4n-5-\left(-3+m^{2}\right)\right)$$

I ddod o hyd i wrthwyneb -3+m^{2}, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-\left(m^{2}+4n-5+3-m^{2}\right)$$

Adio -5 a 3 i gael -2.

$$7m^{2}-5-\left(m^{2}+4n-2-m^{2}\right)$$

Cyfuno m^{2} a -m^{2} i gael 0.

$$7m^{2}-5-\left(4n-2\right)$$

I ddod o hyd i wrthwyneb 4n-2, dewch o hyd i wrthwyneb pob term.

$$7m^{2}-5-4n+2$$

Adio -5 a 2 i gael -3.

$$7m^{2}-3-4n$$