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﻿50 Factorising Quadratics Factorise the quadratics first, and then solve the equations: a) 2x2 - 5x - 12 = 0 d) 24x2 - 34x + 12 = 0 g) 10x2 - 17x + 3 = 0 b) 12x2 - 17x - 5 = 0 e) 6x2 - 2x - 4 = 0 h) 9x2- 3x - 6 = 0 c) 2x2 - x - 36 = 0 1) 4x2 + 3x - 10 = 0 i) 5x2 + 4x - 12 = 0. Q10 Q11 Q12 Rearrange into the form "x2 + bx + c = 0", then solve by factorising: d) 6x2 = 18x g) 15x = 22 - 13- x e) 3(2x2 + 3x - 5) = 0 h) 5x + 16 + 1 =0 a) 3x2 = 2 + x b) 4x(x - 2) = -3 c) 2x(10x + 9) + 4 = 0 0 7x + 5 = 2 x These two shapes have equal areas. Find the value of x. X cm X cm 2x cm 2x cm 3x cm 3 cm 3x cm (5 — x) cm i) 6x2 = 8(x + 1) A photo has a length of 1 cm. Its width is i cm shorter than the length. a) Write down an expression for the area of the photo. b) The photo is enlarged using a scale factor of 4. i) Write an expression for the area of the enlarged photo. ii) The area of the enlarged photo is 340 cm2. Work out the value of 1. a) b) c) Simplify the following fractions by factorising first. 4x + 12 x2+ 8x + 15 x2+ 2x x2 - x - 6 2x2 - 12x x2 - 3x - 18 (ID x2 — 3x + 2 0 6x2 + x — 1 ' xy - 2y 3x2 + 5x - 2 (x + 2)2) 2x2 + x - 3 e) x2 - x - 6 h 2x2 + 9(x + 1) 2x2+ 7x + 3 6(x2 - 2) + x 2x2 - x - 1 i) 9(x2 - x) - 4 SECTION THREE — ALGEBRA