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:
85 miles.
Step-by-step explanation:
Lets begin by figuring out the number of miles in 4 inches. Since every 2 inches make 40 miles, we can figure out that there are 80 miles in 4 inches. To figure out that .125 part, we multiply 40 by .125, to get 5. We can add 80 plus 5 to get our grand total of 85 miles.
Answer:
no b 11 sq.units is the answer
I'll solve 21, and you then should be able to solve the rest on your own!
Since ADC is 135, that means that that whole angle is 135 degrees. In addition, since angles ADB and BDC add up to ADC, we get ADB+BDC=ADC=135=11x+9+7x=18x+9. Subtracting 9 from both sides, we get 126=18x. Dividing both sides by 18, we get x=7. Plugging that into 11x+9=BDC, we get 11*7+9=77+9=86
Y=-x+5
Y=2x-4
X would be your slope
Y intercepts would be (0, 5) , ( 0,-4)
Formula i used was Y=Mx+B
