Question 16:

• WAEC 2018

If the determinant of the matrix \(\begin{pmatrix} 2 & x \\ 3 & 5 \end{pmatrix} = 13\), find the value of x.

A. -2
B. -1
C. 1
D. 2

Question 17:

• WAEC 2018

Express \(\frac{13}{4}\pi\) radians in degrees.

A. 495°
B. 225°
C. 585°
D. 135°

Question 18:

• WAEC 2018

Find the equation to the circle \(x^{2} + y^{2} - 4x - 2y = 0\) at the point (1, 3).

A. 2y - x -5 = 0
B. 2y + x - 5 = 0
C. 2y + x + 5 = 0
D. 2y - x + 5 = 0

Question 19:

• WAEC 2018

The midpoint of M(4, -1) and N(x, y) is P(3, -4). Find the coordinates of N.

A. (2, -3)
B. (2, -7)
C. (-1, -3)
D. (-10, -7)

Question 20:

• WAEC 2018

Given that \(y = x(x + 1)^{2}\), calculate the maximum value of y.

A. -2
B. Zero
C. 1
D. 2