Answer:
x=2
Step-by-step explanation:
4( 2+x) = 18-x
8 + 4x = 18 - x
4x+x = 18-8
5x= 10
x=2
It grows 1.68m because 0.14m times 12
Answer:
There is just one simple rules for find other side
Step-by-step explanation:
Think about a triangle and this triangle has 3 side it must have 90° on one edge. We assume the longest side is hipotenus x²+y²=hipotenus² . Look at your question hipotenus is 15 lets try to find other side. X²+12²=15² x=9
Answer:

Step-by-step explanation:
=> 
=> 
<u><em>Cancelling (x-1)</em></u>
=> 
=> 
Answer: C, 420
Step-by-step explanation:
The first positive even numbers are from 2 to 40, so the sum is equal to the number of terms, times the number of terms plus one (20*21 = 420)
the sum is 420