Text Factorise by taking out the common factor: (a) 7x+287x+287x+28 (b) 4a+10ab4a+10ab4a+10ab (c) 6x2−15x6x^{2}-15x6x2−15x Solution (a) 7x+28=7(x+4)7x+28=7(x+4)7x+28=7(x+4). (b) 4a+10ab=2a(2+5b)4a+10ab=2a(2+5b)4a+10ab=2a(2+5b). (c) 6x2−15x=3x(2x−5)6x^{2}-15x=3x(2x-5)6x2−15x=3x(2x−5). (a) 7(x+4)(b) 2a(2+5b)(c) 3x(2x−5) \boxed{\;(a)\;7(x+4)\qquad (b)\;2a(2+5b)\qquad (c)\;3x(2x-5)\;}(a)7(x+4)(b)2a(2+5b)(c)3x(2x−5)