WAEC Past Questions and Answers - Page 1041

5,201.

A circle with centre (5,-4) passes through the point (5, 0). Find its equation.

A.

x\(^2\) + y\(^2\) + 10x + 8y + 25 =0

B.

x\(^2\) + y\(^2\) +10x - 8y - 25 = 0

C.

x\(^2\) + y\(^2\) - 10x + 8y + 25 =0

D.

x\(^2\) + y\(^2\) -10x - 8y - 25 = 0

Correct answer is C

(x - h)\(^2\) + (y - k)\(^2\) = r\(^2\)

x\(^2\) - 2hx + y\(^2\) - 2ky + h\(^2\) + k\(^2\) = r\(^2\)

x\(^2\) - 2(3)x + y\(^2\) - 2(-4) y + 5\(^2\) + (-4)\(^2\) = r\(^2\)

x\(^2\) - 10x + y\(^2\) + 8y + 25 + 16 = r\(^2\)

x\(^2\) - 10x + y\(^2\) + 8y + 41 = r\(^2\)

at point (5,0)

5\(^2\) - 10(5) + 0\(^2\) + 8(0) + 41 = r\(^2\) 

25 - 50 + 41 = r\(^2\)

16 = r\(^2\) 

r = \(\sqrt{16}\) 

= 4 

x\(^2\) + y\(^2\) - 10x + 8y + 25 = 0

5,202.

Find the nth term of the linear sequence (A.P) (5y + 1), ( 2y + 1), (1- y),...

A.

(8 + 3n)y + 1

B.

8y + 3n + 1

C.

(8 - 3n)y + 1

D.

8y - 3n + 1

Correct answer is C

Tn = a + (n - 1)d

Tn = 5y + 1 (n - 1) -3y

Tn = 5y + 1 - 3ny + 3y 

Tn = 8y - 3ny + 1

Tn = (8 - 3n) y + 1

5,203.

If the binomial expansion of (1 + 3x)\(^6\) is used to evaluate (0.97)\(^6\), find the value of x. 

A.

0.03

B.

0.01

C.

-0.01

D.

-0.03

Correct answer is C

(1 + 3x )\(^6\) = (0.97)\(^6\) 

1 + 3x = 0.97 

3x = 0.97.1

\(\frac{3x}{3} = \frac{0.03}{3}\)

x = -0.01

5,204.

A sale of goods to audu was not posted. This is an error of

A.

Omission

B.

Compensation

C.

Commission

D.

Principle

Correct answer is A

No explanation has been provided for this answer.

5,205.