a) (a-2)(a+3)-(5-a)(4+a) = (2-2)(2+3)-(5-2)(4+2) = 05 - 36 = 0 - 18 = -18
б) 5a^2 - 10ab + 5b^2 при a^2 = 124, b = 245124 - 1012424 + 524^2620 - 29760 + 2880620 - 26880= -26260
a) (a-2)(a+3)-(5-a)(4+a) = (2-2)(2+3)-(5-2)(4+2) = 05 - 36 = 0 - 18 = -18
б) 5a^2 - 10ab + 5b^2 при a^2 = 124, b = 24
5124 - 1012424 + 524^2
620 - 29760 + 2880
620 - 26880
= -26260