HELP ASAP PLS ILL GIVE BRANLIEST GEOMETRY

Gauss' method for addition relies on the fact that you can 'pair' certain numbers together. Look at the example:

1+2+3+4+5+6+7+8+9+10

We could manually add all these together from left to right but a clever way to think about this is if we add together the ends of the sum (10+1) we get 11. If we then move one in from the ends and add these (2+9) we also get 11. This means that 1+2+...+9+10 is the same as 11+11+...+11+11.

Because each 2 numbers adds to 11 we know the total number of 11's we have to add together is the length of the sum divided by 2. In our case 5 (10 ÷ 2). We need to add 5 lots of 11 to get our answer. This is the same as 11 × 5 which is easily seen to be 55.

(If you add the 10 numbers together on a calculator you'll see 1+2+3+4+5+6+7+8+9+10 = 55) so this method really makes it a lot quicker.

Looking at your sequence, if we pair the ends together we get 401 (400+1) and we multiply this by the length of the sequence divided by 2. In your case, 200 (400 ÷ 2).

So the sum of all the numbers from 1 to 400 must be 401 × 200 = 80,200.

Remember the steps:
1. Pair the ends together and add them
2. Times this number by the length of the sequence halved

Hope this helps.

6 0

3 years ago

How do I figure the equation out

Tatiana [17]

Answer:

Answer for Parallel line: y = 3x - 13

Answer for Perpendicular line: y = (-1/3)x +17/3

Step-by-step explanation:

Parallel line

For the slope of a line parallel to another (given) line, just read the slope of the given line. It (in this case) is the coefficient in front of the x.

m = 3

So far what you have is y = 3x + b

To find b, use the given point (2,5)

x = 2

y = 5 Substitute these values into the skeletal equation. y = 3x + b

2 = 3*5 + b Subtract 15 from both sides.

2 = 15 + b

2 - 15 = b switch sides

b = - 13

Answer y = 3x - 13

Part B

Perpendicular line

The perpendicular line will have a slope determined by the following formula

m1 * m2 = - 1

m1 is the slope of the given line which is 3

3 * m2 = - 1

m2 = - 1/3

So far, what you have is

y = (-1/3)x + b To find b, use the same 2 givens as above.

y = 5

x = 2

Substitute into the skeletal equation.

5 = (-1/3)(2) + b

5 = -2/3 + b Switch sides.

b - 2/3 = 5 Add 2/3 to both sides.

b = 5 + 2/3

b = 5 2/3 = 17 / 3

Answer

y = (-1/3)x + 17/3

If this doesn't seem right, and you have choices, could you please list them?

4 0

3 years ago

Can someone give me the answer it’s due tomorrow!!!

Ilya [14]

Answer:

Step-by-step explanation:

x= −3y−18 /2

6 0

3 years ago

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