Given:
Choose a number between 0 and 20.
If the difference is less than 10 then Eric wins.
Let us x is Eric's number. 0 <u><</u> x <u><</u> 20
If Eric wins. |x -7| < 10
|x-7| < 10 → -10 < x-7 < 10 → -10 + 7 < x - 7 + 7 < 10 + 7 → -3 < x < 17
Taking into account that the number must be given between 0 and 20.
0 <u><</u> x <u><</u> 20
-3 < x < 17
→ 0 < x < 16
Answer:
<h2>A = 52.5 m²</h2>
Step-by-step explanation:
The formula of an area of a kite:
<em>e, f</em><em> - diagonals</em>
<em />
We have <em>e = 15m, f = 7m.</em>
Substitute:
This problem is an example of an arithmetic series.
The common difference of the second term (15) with the first term (9) and the third term (21) with the second term (15) [15-9=6; 21-15=6] is 6.
The formula for solving this is:
An= A1 +(n-1)*d where An is the nth term, A1 is the first term, n is the number of terms and d is the common difference.
An=9+ (31-1)*6 = 189
The answer is 189.
