Answer:
22
Step-by-step explanation:
Each number in the sum is even, so we can remove a factor of 2.
2 + 4 + 6 + 8 + ... + 78 + 80 = 2 (1 + 2 + 3 + 4 + ... + 39 + 40)
Use whatever technique you used in (a) and (b) to compute the sum
1 + 2 + 3 + 4 + ... + 39 + 40
With Gauss's method, for instance, we have
S = 1 + 2 + 3 + ... + 38 + 39 + 40
S = 40 + 39 + 38 + ... + 3 + 2 + 1
2S = (1 + 40) + (2 + 39) + ... + (39 + 2) + (40 + 1) = 40×41
S = 20×21 = 420
Then the sum you want is 2×420 = 840.
Answer:
Parallel.
Step-by-step explanation:
Let's find the slope of each line.
One through the points (3,2) and (6,8):-
Slope = rise / run = (8-2)/(6-3)
= 6/3 = 2
The other line:-
Slope = (6-2)(2-0)
= 4/2 = 2
The slopes are the same so the 2 lines are parallel.
widest to narrowest: y=3/2x2, y= -1/2x2, y= 1/4x2
Equalizw the denominators so that the nominators will be equal in this wat sonyou can find the value of x if you want i can solve it
