Answer:

Step-by-step explanation:
a = 3, b = 5, c = 1
plug into quadratic formula
First let's find the length of the last side. We can do this by adding AB and BC together, then subtracting this amount from the perimeter of Triangle ABC, 22 cm.
ABC - (AB + BC) ⇒ 22cm - (8cm + 5cm)
22cm - 13cm = 9cm
The hypotenuse is always the longest side of a triangle, so we know that the side we figured out is the hypotenuse. Now we can use the Pythagorean Theorem to see whether the triangle is a right triangle.
Pythagorean Theorem: a² + b² = c², where a and b are legs and c is the hypotenuse.
If a² + b² do equal c², then the triangle is a right triangle.
8² + 5² = 9²
64 + 25 = 81
89 > 81
The triangle is not a right triangle, but we know that it is obtuse since a and b together are longer than c.
Answer:
30
Step-by-step explanation:
For a = <xa, ya> and b = <xb, yb>, the dot product is the sum of products ...
a·b = (xa)(xb) + (ya)(yb)
Substituting the given information, you have ...
a·b = 5·4 + 2·5 = 20 + 10
a·b = 30
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Some graphing calculators can do such math. There are also dot product calculators available on the Internet. If you have quite a few of these to calculate, you can put the appropriate formula into a spreadsheet.
You can ask Siri. Answer is Increased 75%. “What percent is 56 out of 32.”