To solve this problem, we need to use the Pythagorean Theorem, which states that a^2 + b^2 must equal c^2. "a" is the length of one of the legs (shorter sides of the triangle) and "b" is the length of the other leg. "c" is the length of the hypotenuse.
a = y = 36.25cm
b = x = 20.93cm
a^2 + b^2 = c^2
(36.25)^2 + (20.93)^2 = c^2
1314.0625 + 438.0649 = c^2
√1752.1274 = √c^2
c = 41.8584209 ≈ 41.86
So your final answer is...
The length of the hypotenuse is about 41.86 cm.
Well, we could try adding up odd numbers, and look to see when we reach 400. But I'm hoping to find an easier way.
First of all ... I'm not sure this will help, but let's stop and notice it anyway ...
An odd number of odd numbers (like 1, 3, 5) add up to an odd number, but
an even number of odd numbers (like 1,3,5,7) add up to an even number.
So if the sum is going to be exactly 400, then there will have to be an even
number of items in the set.
Now, let's put down an even number of odd numbers to work with,and see
what we can notice about them:
1, 3, 5, 7, 9, 11, 13, 15 .
Number of items in the set . . . 8
Sum of all the items in the set . . . 64
Hmmm. That's interesting. 64 happens to be the square of 8 .
Do you think that might be all there is to it ?
Let's check it out:
Even-numbered lists of odd numbers:
1, 3 Items = 2, Sum = 4
1, 3, 5, 7 Items = 4, Sum = 16
1, 3, 5, 7, 9, 11 Items = 6, Sum = 36
1, 3, 5, 7, 9, 11, 13, 15 . . Items = 8, Sum = 64 .
Amazing ! The sum is always the square of the number of items in the set !
For a sum of 400 ... which just happens to be the square of 20,
we just need the <em><u>first 20 consecutive odd numbers</u></em>.
I slogged through it on my calculator, and it's true.
I never knew this before. It seems to be something valuable
to keep in my tool-box (and cherish always).
Answer:
x=2, y=13
Step-by-step explanation:
In order to get this by addition which is the easiest way for this you want to take both equations
y=3x+7 and y=-4x+21 and move x to the other side of the equation so it is like 4x+y=21 and -3x+y=7 like that now you have to get rid of one of the exponents and the easiest one to get rid of is y so I'm going to multiply -3x+y=7 by negative 1 so it becomes 3x-y=-7 that way the equations value has not changed since I multiplied both sides and now when I add
4x+y=21 and 3x-y=-7 It'll look like
4x+y=21
3x-y=-7 add those It will get rid of the y
then get 7x=14 simplify to get x=2 then you can take -3x+y=7 plug in x and get
-3(2)+y=7 multiply into -6+y=7 then simplify you get y=13
Answer:
D. 100°
Step-by-step explanation:
A straight line is 180°. Add 50° and 30° (which is 80°) and subtract the total from 180°.
50 + 30 = 80
180 - 80 = 100
