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2 years ago

Question 12. Is the one I need help on

Mathematics

1 answer:

Mekhanik [1.2K]2 years ago

6 0

Four Answers:

Choice A
Choice C
Choice D
Choice J

====================================================

Explanation:

A rational number is any fraction of two whole numbers.

Examples: 7/9 and -8/12

This can be extended to some numbers like $\sqrt{49}$ because

$\sqrt{49} = \sqrt{7^2} = 7 = \frac{7}{1}$

As you can see, any whole number is also rational but not the other way around.

So far, these examples help show that choices A, C, D, and J are rational numbers. Choice D might need a bit of rewriting like so:

$\frac{0.5}{8} = 0.5 \div 8\\\\ = \frac{1}{2} \div \frac{1}{8} \\\\= \frac{1}{2} \times \frac{8}{1}\\\\ = \frac{8}{2}\\\\ = 4$

In short, the expression for choice D simplifies to 4 = 4/1 showing that is rational. Or you can use the shortcut that rational/rational = rational.

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A number like $\sqrt{13}$ is NOT rational because the 13 is not a perfect square. There's no way to rewrite that square root as a ratio or fraction of integers. This allows us to rule out choice B. Choices E, F, and G are eliminated for similar reasoning.

Choice H is ruled out because circle areas involve pi = 3.14159... which is famously an irrational number. The proof of which is very lengthy to go over, but the short version is the decimal digits go on forever without a pattern. This is an informal way to check if we have an irrational number.

Choice I is only eliminated if and only if the side lengths of the square are rational, and also when the side lengths are whole numbers. Its not clear what your teacher's intentions here are, but I'll assume this is the case.

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To summarize, we eliminated B, E, F, G, H, I

We're left with <u>A, C, D, J as the final answers</u>. They either can be written as fractions of integers, or already are fractions of integers.

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PLEASE HELP!!! BRAINLIEST TO CORRECT COMPLETE ANSWER!

notka56 [123]

Answer:

y=16x+1

Step-by-step explanation:

You want to find the equation for a line that passes through the two points:

(1,17) and (2,33).

First of all, remember what the equation of a line is:

y = mx+b

Where:

m is the slope, and

b is the y-intercept

First, let's find what m is, the slope of the line...

The slope of a line is a measure of how fast the line "goes up" or "goes down". A large slope means the line goes up or down really fast (a very steep line). Small slopes means the line isn't very steep. A slope of zero means the line has no steepness at all; it is perfectly horizontal.

For lines like these, the slope is always defined as "the change in y over the change in x" or, in equation form:

So what we need now are the two points you gave that the line passes through. Let's call the first point you gave, (1,17), point #1, so the x and y numbers given will be called x1 and y1. Or, x1=1 and y1=17.

Also, let's call the second point you gave, (2,33), point #2, so the x and y numbers here will be called x2 and y2. Or, x2=2 and y2=33.

Now, just plug the numbers into the formula for m above, like this:

33 - 17/ 2 - 1

or...

m= 16/ 1

or...

m=16

So, we have the first piece to finding the equation of this line, and we can fill it into y=mx+b like this:

y=16x+b

Now, what about b, the y-intercept?

To find b, think about what your (x,y) points mean:

(1,17). When x of the line is 1, y of the line must be 17.

(2,33). When x of the line is 2, y of the line must be 33.

Because you said the line passes through each one of these two points, right?

Now, look at our line's equation so far: y=16x+b. b is what we want, the 16 is already set and x and y are just two "free variables" sitting there. We can plug anything we want in for x and y here, but we want the equation for the line that specfically passes through the two points (1,17) and (2,33).

So, why not plug in for x and y from one of our (x,y) points that we know the line passes through? This will allow us to solve for b for the particular line that passes through the two points you gave!.

You can use either (x,y) point you want..the answer will be the same:

(1,17). y=mx+b or 17=16 × 1+b, or solving for b: b=17-(16)(1). b=1.

(2,33). y=mx+b or 33=16 × 2+b, or solving for b: b=33-(16)(2). b=1.

See! In both cases we got the same value for b. And this completes our problem.

The equation of the line that passes through the points

(1,17) and (2,33) is y=16x+1

4 0

3 years ago

Solve for g. C = d/g

icang [17]

Answer:

I believe that g=dc

Step-by-step explanation:

You swap positions with g and c along with their sign of operation.

7 0

3 years ago

a shopkeeper sold a certain number ( a two-digit number)of toys all priced at a certain value (also a two-digit number when expr

Makovka662 [10]

The answer is 91 toys sold, make the number ab where a is the 10th digit and b is the first digit. The value is 10a + b that can expressed as 10 (3) + 4 = 34

Let the price of each item: xy

10x + y

He accidentally reversed the digits to: 10b + a toys sold at 10y + x rupees per toy. To get use the formula, he sold 10a + b toys but thought he sold 10b + a toys. The number of toys that he thought he left over was 72 items more than the actual amount of toys left over. So he sold 72 more toys than he thought:

10a + b =10b + a +72

9a = 9b + 72

a = b + 8

The only numbers that could work are a = 9 and b = 1 since a and b each have to be 1 digit numbers. He reversed the digits and thought he sold 19 toys. So the actual number of toys sold was 10a + b = 10 (9) + 1 = 91 toys sold. By checking, he sold 91 – 19 = 72 toys more than the amount that he though the sold. As a result, the number of toys he thought he left over was 72 more than the actual amount left over as was stated in the question.

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3 years ago

Cyclic quadrilateral.

ad-work [718]

What do you mean, you need more information in your queston p,ease try to ask it again, it makes no Sence

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4 years ago

Read 2 more answers

Really need help Pls

Studentka2010 [4]

Answer:

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