Question
In the given figure, the directed lines are parallel to each other. Find the unknown angles.
✓
Answer
From 0, draw a line parallel to the given parallel lines
∴ ∠1 = 50° .......(alternate angles)
∠2 = 40°
∴ b = ∠1 + ∠2 = 50° + 40° = 90°
But a + b = 360° ........(angles at a point)
∴ a + 90° = 360°
⇒ a = 360°− 90° = 270°
Hence a = 270°, b = 90°
∴ ∠1 = 50° .......(alternate angles)
∠2 = 40°
∴ b = ∠1 + ∠2 = 50° + 40° = 90°
But a + b = 360° ........(angles at a point)
∴ a + 90° = 360°
⇒ a = 360°− 90° = 270°
Hence a = 270°, b = 90°
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
If $1 \frac{1}{4}: 2 \frac{1}{3}=p: q$ and $q: r=4 \frac{1}{2}: 5 \frac{1}{4} ;$ find $p: r$.
→Arrange the given rational numbers in descending order:
$\frac{5}{8}, \frac{13}{-16} \text { and } \frac{-7}{12}$
→$\frac{5}{8}, \frac{13}{-16} \text { and } \frac{-7}{12}$
Simplify: $5 \frac{3}{4}-\frac{3}{7} \times 15 \frac{3}{4}+2 \frac{2}{35} \div 1 \frac{11}{25}$
→Read the given bar graph and answer the questions that follow :
(i) What information is represented by the bar graph?
(ii) How many marks were obtained in English?
(iii) In which subject least marks were obtained?
(iv) What was the total marks obtained in all the subjects together?
(i) What information is represented by the bar graph?
(ii) How many marks were obtained in English?
(iii) In which subject least marks were obtained?
(iv) What was the total marks obtained in all the subjects together?
Evaluate: $(a + 5)(3a - 2)(5a + 1)$
→On selling an article for Rs. 2,640, a profit of 10 percent is made. Find
(i) cost price of the article
(ii) new selling price of it, in order to gain 15%
(i) cost price of the article
(ii) new selling price of it, in order to gain 15%
Insert three fractions between $\frac{3}{8}$ and $\frac{6}{11}$
→If the price of an article is increased by 25%, The increase is Rs. 10. Find a new price.
$35-[15+\{14-(13+\overline{2-1+3})\}]$
→