3.(2x+5)-(x-3) 4.a²+2ab-3b²-7a³-5ab 5.x²-x-6+3x-xy pleasss sekarrang yaa!

3)
(2x + 5) - (x - 3)
= 2x + 5 - x + 3
= 2x - x + 5 + 3
= x + 8

4)
a² + 2ab - 3b² - 7a³ - 5ab
= -7a³ + a² + 2ab - 5ab - 3b²
= -7a³ + a² - 3ab - 3b²
= -(7a³ - a² + 3ab + 3b²)

5)
x² - x - 6 + 3x - xy
= x² - x + 3x - xy - 6
= x² + 2x - xy - 6