Mathematics questions and answers

Mathematics Questions and Answers

How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.

486.

If \(\begin{vmatrix} 2 & -4 \\ x & 9 \end{vmatrix} = 58\), find the value of x.

A.

10

B.

30

C.

14

D.

28

Correct answer is A

\(\begin{vmatrix} 2 & -4 \\ x & 9 \end{vmatrix} = 58\)

\(\implies (2 \times 9) - (-4 \times x) = 58\)

\(18 + 4x = 58 \implies 4x = 58 - 18 = 40\)

\(x = 10\)

487.

If P(2, m) is the midpoint of the line joining Q(m, n) and R(n, -4), find the values of m and n.

A.

m = 0, n = 4

B.

m = 4, n = 0

C.

m = 2, n = 2

D.

m = -2, n = 4

Correct answer is A

Q(m, n) and R(n, -4)

Midpoint : P(2, m)

\(\implies (\frac{m + n}{2}, \frac{n - 4}{2}) = (2, m)\)

\(m + n = 2 \times 2 \implies m + n = 4 ... (i)\)

\(n - 4 = 2 \times m \implies n - 4 = 2m ... (ii)\)

Solving (i) and (ii) simultaneously,

m = 0 and n = 4.

488.

If given two points A(3, 12) and B(5, 22) on a x-y plane. Find the equation of the straight line with intercept at 2.

A.

y = 5x + 2

B.

y = 5x + 3

C.

y = 12x + 2

D.

y = 22x + 3

Correct answer is A

The equation of a straight line is given as \(y = mx + b\) 

where m = the slope of the line

b = intercept

Given points A(3, 12) and B(5, 22), the slope = \(\frac{22 - 12}{5 - 3}\)

= \(\frac{10}{2}\) = 5

Hence, the equation of the line is \(y = 5x + 2\).

490.

In the figure above, |CD| is the base of the triangle CDE. Find the area of the figure to the nearest whole number.

A.

56 cm\(^2\)

B.

24 cm\(^2\)

C.

42 cm\(^2\)

D.

34 cm\(^2\)

Correct answer is D

Area of rectangle ABCD = length x breadth

= 7 x 4 

= 28 cm\(^2\)

Area of triangle CDE = \(\frac{1}{2}\) base x height

= \(\frac{1}{2} \times 3 \times 4\)

= 6 cm\(^2\)

Area of the figure = 28 cm\(^2\) + 6 cm\(^2\)

= 34 cm\(^2\)