M = 3rt^2 - 2rv
2rv = 3rt^2 - M
v = (3rt^2 - M)/2r
Correct answer:
"<span>If the sum of the squares of the two shorter sides equals the square of the longest side, then the triangle is a right triangle"
the Pythagorean theorem states that in a right triangle, the sum of the squares of the shortest sides is equal to the square of the largest side, the hypotenuse.
Also,
If we have a triangle with side lengths a, b and c, where a and b are the shortest, and "a squared plus b squared = c squared" then the triangle is a right triangle.
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Focus has coordinates (0, a)
a = -3
Thus, 4a = 4(-3) = -12
Because a is negative, we know it will be a concave down or concave left parabola. Hence, A and D can be eliminated. And we know it has to be B because the directrix is the horizontal line y = 3. Hence, the equation of the parabola becomes:

or
An absolute value inequality for "all numbers less than 7 and greater than -7" is given by |x| < 7.
<h3>How to write an absolute value inequality?</h3>
Based on the information provided, we can logically deduce that the statement describes an intersection of set because the word "and" was used.
This ultimately implies that, we would use the less than (<) symbol to write an absolute value inequality for the given statement:
|x| < 7
Therefore, this can be translated as follows:
-7 < x < 7 or x < 7 and x > -7.
Read more on number line here: brainly.com/question/24644930
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