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3 years ago

Factor-20x2 + 13x + 21. How do you solve this

Mathematics

1 answer:

zaharov [31]3 years ago

5 0

Answer:

-3(9x-7)

Step-by-step explanation:

first multiply

20x2=40

and now its -40x+13x+21

then add same variables

-40x+13x=-27x

now its -27x+21

then rewrite the equation

3 x 7=21

-3 x 9x = 27x

now its (-3 x 9x) + (3 x 7)

then the multiply thingy and you got the answer

You might be interested in

49.5 is what percent of 33?

stira [4]

49.5/33 x 100= 150%. This is also rather simple to figure out just by looking at the question itself, you can clearly see that 49.5 is 16.5 greater than 33 and that 16.5 is half of 33. Which you can easily figure out from there.

6 0

4 years ago

A cat keeps eating to gain weight while a dog keeps doing exercise.Later, the cat's weight increases by 20% and the dog's weight

lesya [120]

Answer:

Step-by-step explanation:

We will call the dog's original weight d and the cat's c. according to the problem 1.2c=.9d

1.2c is the cat's weight increased by 20% and .9d is the dog's weight decreased by 10% Now we just solve this with algebra for the dog's original weight.

1.2c=.9d

(1.2/.9)c = d

(4/3)c = d

Now, this tells us that the dog's original weight was 4/3 of the cat's.or about 33.33% larger

It kinda looks like the question is then asking what the cat's current weight is in comparison to the dog's original. If that's the case we need just one more step. We want the dog's original weight and the cat's current weight in terms of the same variable. Well, we have that.

Current cat = 1.2c or 6/5, since we have the other in fractional form.

original dog = (4/3)c

Now, what do we multiply the first to get to the second? Well, we need common denominators. 15 is the lcm of 3 and 5, so we'll use that.

6/5 = 18/15 and 4/3 = 20/15

Nowwe want to know what we have to multiply 18 by to get to 20. some algebra will find that.

18x=20

x = 20/18

x = 10/9

that's about 1.11, so the dog's original weight is about 11% higher than the cat's current weight.

Hopefully that's the answer it wanted, if not or if there is something you didn't understand let me know.

7 0

3 years ago

Solve (x-3)^2 = 5 HELP ASAP!!! Please!! :(

Bas_tet [7]

Answer:

Answer is option d 

Step-by-step explanation:

$given \: expression \: is \: {(x - 3)}^{2} = 5 \\ {x}^{2} - 6x + 9 = 5 \\ subtracting \: 5 \: on \: both \: sides \: we \: get \\ {x}^{2} - 6x + 4 = 0 \\ on \: solving \: the \: quadratic \: equation \: by \\ \: completing \: square \: method \\ {x}^{2} - 6x = - 4 \\ adding \: {3}^{2} on \: both \: sides \: w e\: get \\ {x}^{2} - 6x + {3}^{2} = {3}^{2} - 4 \\ {(x - 3)}^{2} = 5 \\ x - 3 + = \sqrt{5} \\ x = \sqrt{5 } + 3$

HAVE A NICE DAY!

THANKS FOR GIVING ME THE OPPORTUNITY TO ANSWER YOUR QUESTION. 

5 0

3 years ago

What is the volume, in cubic feet, of this composite figure? (Do not write

Alenkasestr [34]

I think the answer is 5

8 0

3 years ago

A company that creates steering wheels for cars found that 2 of the steering wheels manufactured each hour yesterday were defect

Ymorist [56]

2 steering wheels manufactured each hour were defected
There were 50 steering wheels manufactured per hour
The fraction is $\frac{2}{50}$
Divide 2, which is the numerator by 50, which is the denominator
2÷50=.04
To change any decimal into a fraction, multiply by 100
The multiply .04 by 100 to change into a percentage
.04×100=4.⇒4%
4% is the percentage of defective steering wheels

7 0

3 years ago