# Mathematics 2020 Past Questions | WAEC

Study the following Mathematics past questions and answers for JAMB, WAEC NECO and Post-JAMB. Get prepared with official past questions and answers for upcoming examinations.

46. The graph of the equations y = 2x + 5 and y = 2×22+ x – 1 are shown below. Find the points of intersection of the two graphs.

**A.**(2.0, 9.0) and (-1.5, 2.0)**B.**(2.0, 8.5) and (-1.5, 2.0)**C.**(2.0, 8.0) and (-1.5, 2.5)**D.**(2.0, 7.5) and (-1.5, 2.5)

**Correct Option: Answer is A**

**47. **The graph of the equations y = 2x + 5 and y = 2x^{2}+ x – 1 are shown. If x = -2.5, what is the value of u on the curve?

**A.**y = 8.0**B.**y = 8.5**C.**y = 9.0**D.**y = 9.5

**Correct Option: Answer is B**

**48. **If (x + 2) is a factor of x^{2}+px – 10, find the value of P.

**A.**3**B.**-3**C.**7**D.**-7

**Correct Option: Answer is B**

x + 2 = 0

x -2

x2 = px – 10 = 0

(-2)2 – 2p – 10 = 0

4 – 2p – 10 = 0

−2p/−2=6/−2 → p = -3

**49. **In the diagram, O is the centre of the circle. If < NLM = 74^{o}, < LMN = 39^{o}and < LOM = x, find the value of x.

**A.**134^{o}**B.**126^{o}**C.**113^{o}**D.**106^{o}

**Correct Option: Answer is A**

LNM = 180^{o} – (74 + 39)^{o}

180^{o} – 113^{o }

= 67^{o}

L^{O}

M = x = 2 x 67^{o}= 134^{o}

**50. **Find the least value of x which satisfies the equation 4x = 7(mod 9)

**A.**7**B.**6**C.**5**D.**4

**Correct Option: Answer is D**

### MATHEMATICS PAST QUESTIONS 2020 THEORY

- (a) If A = {multiples of 2}, B = {multiples of 3} and C = {factors of 6} are subsets of μ= {x:1 ≤x 5 ≤ 10} find A ∩ B ∩ C

(b) Tickets for a movie premiere cost $18.00 each while the bulk purchase price for 5 tickets is $80.00. If 4 gentlemen decide to get a fifth person to join them so that they can share the bulk purchase price equally, how much would each person save?

**Solution & Explanation:**

μ = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

A = {2, 4, 6, 8, 10}

C = {1, 2, 3, 6}

A` ={1, 3, 5, 7, 9}

B` = {1, 2, 4, 5, 7, 8, 10}

C` = {4, 5, 7, 8, 9, 10}

a` ∩ B` C` = {} or ∅

1(b) bulk cost $80

1 will cost $80/5 = $16

for 5 gentlemen each cost $18.50

total cost = 18.50 x 5

= $92.50

5 cost for $16 each = 5 x $16

= $80 – 12.00

each will save $12.50/5

= $2.50

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