Answer:
Multiplication Symbols:
<u>1.</u><u> Times</u> ×
<u>2.</u><u> Dot</u> ⋅
<u>3.</u><u> Parentheses</u> ()
<u>4.</u><u> Variables next to each other</u> <em>ab</em>
Step-by-step explanation:
The symbols can be used like this...
Times: <em>a</em> × <em>b</em> = <em>c</em>
Dot: <em>a</em> ⋅ <em>b</em> = <em>c</em>
Parentheses:<em> </em>(<em>a</em>)(<em>b</em>) = <em>c</em>
Variables next to each other: <em>ab </em>= <em>c</em>
Answer: There are 108 hammers, and there are 36 screwdrivers. 36×3=108·
Step-by-step explanation: We know that there are more hammers than screwdrivers, so there are 36 screwdrivers but there are 3 times as many hammers so we multiply 36 by 3 to get 108.
Answer:
175 ways
Step-by-step explanation:
5 balls are red, and 7 balls are blue making a total of 12 balls.
4 balls are drawn from the box,
1 ball is red and 3 balls are blue out of the 4 drawn from the box.
We have to choose 1 ball from 5 red balls and 3 blue balls from 7 blue balls.
Since the order is not essential we use combinations to find out
5C1 * 7C3= 5*35 = 175 ways
Let's go through the choices one by one
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Choice A
If all sides are congruent, then this figure is a rhombus (by definition). If all angles are congruent, then we have a rectangle. Combine the properties of a rhombus with the properties of a rectangle and we have a square.
In terms of "algebra", you can think
rhombus+rectangle = square
Or you can draw out a venn diagram. One circle represents the set of all rhombuses; another circle represents the set of all rectangles. The overlapping region is the set of all squares. The overlapping region is inside both circles at the same time.
So we can rule out choice A. This guarantees we have a square when we want something that isn't a guarantee.
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Choice B
If we had a parallelogram with perpendicular diagonals, then we can prove that we have a rhombus (all four sides congruent). However, we don't know anything about the four angles of this parallelogram. Are they congruent? We don't know. So we can't prove this figure is a rectangle. The best we can say is that it's a rhombus. It may or may not be a rectangle. There isn't enough info about the rectangle & square part.
This is why choice B is the answer. We have some info, but not enough to be guaranteed everytime.
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Choice C
This is a repeat of choice A. Having "all right angles" is the same as saying "all angles congruent". This is because "right angle" is the same as saying "90 degrees". So we can rule out choice C for identical reasons as we did with choice A.
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Choice D
As mentioned before in choice A, if we know that a quadrilateral is a rectangle and a rhombus at the same time, then the figure is also a square. This is always true, so we are guaranteed to have a square. We can cross choice D off the list.
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Once again, the final answer is choice B
Answer:
First one
Step-by-step explanation:
None of the equations are identities
