AnSWErS to tHE StudEnt'S Book ExErCiSES - Hodder Plus Home

3 a)42510y50y 2x 2 3x 9y 1y 5b) (i) x 5 22.9 or 1.4 (ii) x 5 22.4 or 0.94 a) y3025 y x 2 5x 320151052y 2x2 0 2 4 6 85xy 5b) (i) x 5 0.7 or 4.3 (ii) x 5 20.4 or 5.4(iii) x 5 0.5 or 6.55 y 5 246 y 5 2x 2 1 4x 2 3Exercise 16.4 (page 227)1 a)42604020204060yy x 3y 4x0 2 4b) x 5 22, 0 or 2c) yy x 3 4x15103 2 1 0 1 2 3510152 a) Year Number of birds (n)1970 50 0001980 40 0001990 32 0002000 25 6002010 20 4805xxxb)n50 00040 00030 00020 00010 000n 50 000 0.8 y01970 1980 1990 2000 2010Yearc) n 5 50 000 3 0.8 y where y is the number ofyears from the start (1970)3 a) The table of values is shown.x 24 23 22 21 0 1 2y 16 8 4 2 1 0.5 0.2520y 2 x 151054 2 0 2yb) (i) y 5 0.7(ii) x 5 23.324 a) n 5 2 3 3 y22005b) The missing values for n are 162 and 486.5 a) y35y 2 x302520151052 1 0 1 2 3 4 5b) (i) y 5 9.2(ii) x 5 3.36 a) The table of values is shown.x 24 23 22 21 0 1 2 3 4y 20.75 21 21.5 23 — 3 1.5 1 0.7542b) y 5 1.74224yy 3xx0 2 4xx210Answers to the Student’s Book exercisesHigher WJEC GCSE Mathematics © 2010, Hodder Education