20%, because 20/100 is equal to 20&.
Hope this helps!
Unlike the previous problem, this one requires application of the Law of Cosines. You want to find angle Q when you know the lengths of all 3 sides of the triangle.
Law of Cosines: a^2 = b^2 + c^2 - 2bc cos A
Applying that here:
40^2 = 32^2 + 64^2 - 2(32)(64)cos Q
Do the math. Solve for cos Q, and then find Q in degrees and Q in radians.
Answer:
18,176
Step-by-step explanation:
Figure out an easier thing to do: 1000 - 2021 = 9,797.
Therefore, our answer will be like 9999999999999999999999997979. Out of all of these digits, there are only 2 that arent nines. We know the amount of digits since it's 10^2021 power. We will have one less since we are subtracting 2021. Therefore, 2020 digits in total. Now we know of those 2020 digits, 2 of them are 7, therefore 2018 of them are 9s. That means do 2018(9) + 2(7) = 14 + 18,162 = 18,176.
(b) is the answer.
Step-by-step explanation:
By the Pythagorean Theorem,
A² + B² = C²
Where:
A = Length of side 1
B = Length of side 2
C = Hypotenuse
This rule applies to all right-angled triangles.
The length of the hypotenuse of a right-angled triangle is always the largest value.
Therefore, we can test the answers with the equation above.
(a)
8² + 18² = 20²
64 + 324 = 400
388 ≠ 400
The rule of Pythagorean theorem doesn't work on a, so (a) is not a right-angled triangle.
(b)
12² + 35² = 37²
144 + 1225 = 1369
1369 = 1369
The rule of Pythagorean theorem works here, so (b) is a right-angled triangle.
