<h3>Answer:</h3><h3>There are 3 true statements, and the true statements are: </h3><h3>choice A, choice C, choice D</h3>
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Explanation:
A. True. All triangles have 3 straight sides and 3 angles.
B. False. All triangles are polygons. A polygon is just a collection of line segments glued together to form a closed shape.
C. True. A plane figure is a flat shape.
D. True. See choice A.
E. False. Some triangles do not have one right angle. Example: obtuse triangles do not have any right angles.
Answer: The answer is 4 and 32.
Step-by-step explanation: Let "A", "B" and "C" represents the set of students who were taking Arabic, Bulgarian and Chinese respectively.
The, according to the given information, we have

Let 'p' represents the number of students who take all the three languages, then

Also,

From here, we get after subtracting equation(c) from (b) that
Therefore,
and from equation (a), we find

Thus,
and

Thus, the number of students who take all the three languages is 4 and the number of students who take none of the languages is 100-68 = 32.
Answer:
An equation is a mathematical statement that shows the equal value of two expressions while an inequality is a mathematical statement that shows that an expression is lesser than or more than the other. 2. An equation shows the equality of two variables while an inequality shows the inequality of two variables.
Answer:
a- (3,4)
b- (0,-4)
c- (-6,2)
d- (0,5)
e- (-4,-5)
Step-by-step explanation:
hope this helps