4. Draw two intersecting lines such that one of the angles thus formed is 70°. Find the
measure of the remaining angles formed.
Answers
Answer:
Step-by-step explanation:
Two straight lines intersect each other in such a way that one of the formed angles is 90°.
To find,
Remaining angles are also 90°.
Solution,
Let,the two straight lines = AB and CD
And, their intersection point = O
According,to the data mentioned in the question one of the formed angles is 90°. We marked that 90° angle as ∠BOC. (Shown in diagram below.)
Other three angles are = ∠AOC,∠AOD and ∠BOD.
Now,AB is a straight line. So,the ∠AOB will be 180°.
∠AOC+∠BOC = 180°
∠AOC+90° = 180°
∠AOC = 180°-90°
∠AOC = 90°
We know that,the vertical angles which are created by the intersection of two straight lines,are equal.
In this case, ∠BOC and ∠AOD are vertical angles. And, ∠AOC and ∠BOD are vertical angles.
So,
∠BOC = ∠AOD
∠AOC = ∠BOD
Or,
90° = ∠AOD (By, putting the value.)
90° = ∠BOD (By, putting the value.)
Hence,the remaining angles are also 90°.