Answer:
Explanation:
18. Supplementary angles add up to 180°therefore
∠W+∠V=180°
∠W+49°=180°
∠W=180°-49°
∠W=131°
19.Complementary angles are angles that add up to 360°
∠2+∠3=90°
∠2+56°=90°
∠2=90°-56°
∠2=34°
Vertical angles are equal therefore this tells us that ∠1 and ∠2 are equal
∠1=∠2
∴∠1=34°
20. Angles which are in a linear pair add up to 180°(supplementary)
Mathematically what the statement is sayin is :
∠1+∠2=180°
and ∠1=5(∠2)-18°
therefore we can plug in ∠1=5(∠2)-18° in ∠1+∠2=180°
(5(∠2)-18°)+∠2=180°
5(∠2)+∠2=180°+18°
6(∠2)=192°
∠1=5(33°)-18°
∠1=165°-18°
∠1=147°