The answer is: [C]: Two angles form [a] linear pair if and only if the angles are adjacent.
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{Your answer choice is correct! Good job!}.
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Explanation:
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Consider the answer choice given in: "Answer choice: [C]" :
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"<span>Two angles form linear pair if and only if the angles are adjacent."
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Then, consider the following:
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1) "Two angles that are supplementary form a linear pair."
Is this true? Yes, but not always. (In other words, "sometimes"). A "linear pair" of angles IS supplementary (by definition); however, NOT ALL supplementary pairs of angles are linear angles. Supplementary pairs of angles must ALSO be ADJACENT in order to be "linear angles" as well.
2) "Two angles that are vertical are adjacent." Is this true? No; this is NEVER true
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As such, this biconditional is NOT a good definition; and by examining all the other answer choices given, we see that this answer choice "C" is correct.
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Consider the other answer choices given:
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Answer choice: [A]: "T<span>wo angles are supplementary if and only if the sum of their angles measures 180." ;
</span> is INCORRECT because it is a good definition:
1) If 2 angles are supplementary, then the sum of their measures is 180 degrees.
2) If the sum of the measures of two angles is 180 degrees, then the angles are supplementary.
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Answer choice: [B]: "<span>Two angles are vertical angles only if they are not adjacent to each other and are formed by two intersecting lines.";
is INCORRECT because it is a good definition:
1) </span>If two angles are vertical, then they are nonadjacent angles formed by two intersecting lines.
<span> 2) If two angles are nonadjacent angles formed by two intersecting lines, then the angles are vertical angles.
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Answer choice: [D]: "The sum of two angles is 90 if and only if those angles are complementary" ;
is INCORRECT because it is a good definition:
1) </span>If two angles are complementary, then the sum of their measures is 90 degrees.
<span> 2) f the sum of [the measures of] two angles is 90 degrees, then the angles are complementary.
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Answer:
b
Step-by-step explanation:
d = r * t
None of them are really correct, but the closest one is B. Look at the equation. Rate is multiplied by time. The result is distance.
The 90 minutes should be changed to hours. No speedometer on a car is rated in feet per second.
12(x+3)=4(2x+9)+4x
12x+36=8x+36+4x
12x+36=12x+36
12x=12x
0=0
true for all x
Answer:
He rode <u>20</u><u> </u><u>miles</u><u> </u><u>in</u><u> </u><u>2</u><u> </u><u>hours</u>
There are 260 sunflowers when there were 5 daisies and 100 roses
Given :
the number of daisies varied inversely as the number of sunflowers and directly as the number of roses.
Let 'd' be the daisies and 's' be the sunflowers and 'r' be the roses
Daises varies inversely as sunflowers and directly as roses
So, the equation becomes 
where k is the constant
Lets find out 'k' using the given information
When there 65 daisies, there were 15 roses and 3 sunflowers
d=65, r=154 and s=3. Replace the values and find out k

Replace k with 13 in the equation

Now we find out number of sunflowers using the above equation
d=5 and r=100 . Replace the values and find out 's'

There are 260 sunflowers when there were 5 daisies and 100 roses
Learn more : brainly.ph/question/5828295