Question

PLS how to do this 3 sums

Answer 1

Explanation:

7) PQ // RS, RQ is transversal

x = 38 {Alternate interior angles are congruent}

In ΔPQR ,

x + y + ∠P = 180 {Angle sum property of triangle}

38 + 90 + y = 180

128 + y = 180

y = 180 - 128

y = 52

9) Construct XY // AB

XY // AB & AC is transversal

∠1 = ∠4 ---------(I) {alternate interior angles are equal}

XY // AB & BC is transversal

∠3 = ∠5 ---------(II) {alternate interior angles are equal}

∠1 + ∠2 + ∠3 = 180 {straight line angles}

∠4 + ∠2 + ∠5 = 180 {From (I) & (II) }

Sum of three angles of triangle is 180.Hence proved.