1991 - WAEC Mathematics Past Questions and Answers - page 2

x = \(-\frac{2}{3}\) and \(-\frac{1}{4}\)

\(\implies (x + \frac{2}{3}) = 0; (x + \frac{1}{4}) = 0\)

\((x + \frac{2}{3})(x + \frac{1}{4}) = 0\)

\(x^{2} + \frac{1}{4}x + \frac{2}{3}x + \frac{1}{6} = 0\)

\(x^2 + \frac{11}{12}x + \frac{1}{6} = 0\)

\(12x^2 + 11x + 2 = 0\)

6(x - 4) + 3(x + 7) = 3

6x - 24 + 3x + 21 = 3

9x - 3 = 3

9x = 6

x = \(\frac{2}{3}\)

2x + y = 7 = i
3x - 2y = 3 = ii
i x 2 + ii = 4x + 2y = 14

(\frac {3x - 2y = 3}{7x = 17})

x = (\frac {17}{7}) = 7x = 17 x 1/7 x 7
17 - 10 = 7

r= 4cm; base area = (\pi)r²; Curve S.A = 2(\pi)rh

(\frac{base area}{curved area}) = 1/4; (\pi)/2(\pi)rh

=h = (\frac{4 x 4cm}{2})

h= 8cm

Husband contributions = (\frac{7}{100}) x N5,500 = N385

Wife contribution = (\frac{4}{100}) x N4,000 = N160

Sum of their Annual contribution = N385 + N160 = N545

80km/h = (\frac{80}{60}) x (\frac{1000}{60}) = 3 x 3= (\frac{40 x 5}{9})

= (\frac{200m/s}{9}) = 22.22m/s

Error =12.75 - 7.50 = 5.25

Error % = (\frac{5.25}{12.75}) x 100% = 41.2%

Area of the bigger semi circle P x RO =

P = (\pi)r + (\pi)r + R = (\frac{22}{7}) x 7 + (\frac{22}{7}) x (\frac{7}{2}) + 7

P = 22 + 11 + 7 = 40cm

The region is denoted by 4x + 3y (\geq) 6