Sagot :
Answer:
[tex]1. \: 10b {}^{2} + ( - 7b {}^{2} ) = 3b {}^{2} [/tex]
[tex]2. \: \: 4xy + 8x = 4xy + 8x[/tex]
[tex]3. \: \: 20x {}^{2}y + 50x {}^{2}y = 70x {}^{2}y[/tex]
[tex]4. \: \: 9a + 5b + (7a - 6b) = 16a - b[/tex]
[tex]5. \: \: 5np - 7 {n}^{2} - 8 {p}^{2} + (10np + 20 {n}^{2} + 10p {}^{2}) = 15np + 13n {}^{2} + 2 {p}^{2} [/tex]