2021 SCIENCE QUIZ - SENIOR MATHEMATICS

Solve the equation 2a² – 3a – 27 = 0.

• 3/2, 9

• – 3/2, 9

• 3, 9/2

• – 3, 9/2

Factorize x² + 2a + ax + 2x.

• (x + 2a)(x + 1)

• (x + 2a)(x – 1)

• (x2 – 1)(x – a)

• (x + 2)(x + a)

A rectangle has length x cm and width (x – 1) cm. If the perimeter is 16cm, find the value of x.

• 
  

   $3\ \frac{1}{2}$  cm

• 4cm

• 5cm

• 6cm

Solve the equation 3x + 4y = 5 and 7x + 2y = 8.

• $x\ =\ 2\ \frac{1}{2},\ y\ =\ 4$

• $x\ =\ 4\ \frac{1}{3},\ y\ =\ 3\ \frac{1}{2}$

• $x\ =\ 2\ \frac{1}{4},\ y\ =\ 3\ \frac{1}{5}$

• $x\ =\ 1,\ y\ =\ \frac{1}{2}$

A bag contains 3 black, 4 yellow and 7 red balls. A ball is picked from the bag at random what is the probability that it is white?

• 1

• 
  

  $\frac{7}{14}$

• ¾

• 0

Solve the equation     

 $\frac{2}{x-1\ }$  -  $\frac{3}{x\ +1}$  = 1

• 2 OR – 3

• 2 OR 3

• -2 OR 3

• - 2 OR -3

 $\frac{2x\ +1}{2}\$  -  $\frac{3x\ -\ 7}{9}$  -  $\frac{5}{18}$  

   Simplify

• 2x + 1

•  $\frac{2x\ +3}{3}$  

•  $\frac{2x\ +18}{3}$  

• 2x + 6

If x = 3, y = 2 and z = 4, what is the value of 3x² – 2y + z?

• 17

• 27

• 35

• 71

A fair die is rolled once. What is the probability if obtaining either a 2 or a 5?

• 1/36

• 1/6

• 1/3

• 2/3

 $\frac{\left(12x-2z\right)}{\left(4y\ +\ z\right)}$  

If the numbers x, y, z are in the ratio 6:5:8, find 

• 0

• 8

• 2

• 1