WAEC past questions and answers-Mathematics

Here is a comprehensive guide of the past questions and answers on Mathematics from previous years.Our ScholarsArk team have taken their time to pick out questions that students have difficulty in solving all around West Africa.

1(a).Prove that the sum of the angles of a triangle is two-right angles.(b)In a triangle LMN,the side MN is produced to P and the bisector of <LNP meets ML produced at Q.If <LMN=46° and <MLN=80°,calculate <LQN,stating clearly your reasons.(WASSCE JUNE 1988 THEORY)

SOLUTION

(a)To prove:Â+B+C=2⨉90°=180°

Construction:Produce /BC/ to X and draw a line parallel to /AB/ through C.

Proof:With the lettering of the figure

a1=a2(alternate angles)

b1=b2(corresponding angles)

c + a2 + b2=180°(sum of angles on a straight line)

c + a1 + b1=180°(sum of angles in a ◬ABC)

A + B + C=180°

(b)In ◬LMN,L + M + N=180°(sum of angles in a triangle)

80° + 46°+ LNM=180°

LNM=180°-126°=54°

LNP=LMN + MLN(exterior angle=sum of two interior opposite angles)=80° + 46°=126°

LNQ=QNP(Given that QN is a bisector)

LNQ=126°/2=63°

MNQ=LMN + LNQ=54° + 63°=117°

46° + 117° + LQN=180°

LQN=180° – 163°=17°