Please someone help me and explain this question to me (the last question starting with a straw)
1 answer:
You might be interested in
Answer:
(A) x=40
Step-by-step explanation:
Given: It is given that m is parallel to n.
To find: The value of x.
Proof: It is given that m is parallel to n, from the figure it can be seen that 105° and (3x-15)° forms alternate exterior angles which are equal in measure because m is parallel to n.
Thus,
⇒
⇒
⇒
⇒
Thus, the value of x is 40, hence option A is correct.
Given:
First term of an arithmetic sequence is 2.
Sum of first 15 terms = 292.5
To find:
The common difference.
Solution:
We have,
First term:
Sum of first 15 terms:
The formula of sum of first n terms of an AP is
Where, a is first term and d is common difference.
Putting , n=15 and a=2 in the above formula, we get
Divide both sides by 15.
Dividing both sides by 7, we get
Therefore, the common difference is 2.5.