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3 years ago

R^2+15r+56=0 Quadratics factoring

Mathematics

1 answer:

mylen [45]3 years ago

6 0

Step-by-step explanation:

Find the product, sum and factors which are P=56, S=15 and F=8,7 respectively.

r²+15r+56=0

replacing with the factors in the equation

=> r²+8r+7r+56=0

r(r+8)+7(r+8)=0

(r+8)(r+7)=0

=> r= –8 and –7

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Two possible plans for a new bathroom are shown. Is there a value of x for which the perimeters are equal? Show your work. Expla

Dominik [7]

Answer:

There is no value of x to fit this requirement.

Step-by-step explanation:

The 2 perimeters in terms of x are:

4(x + 3) for the square and

2(x+1) + 2(x +4) for the rectangle

and these need to be equal so

we equate these 2 and solve for x:

4(x + 3) = 2(x+1) + 2(x +4)

4x + 12 = 2x + 2 + 2x + 8

4x + 12 = 4x + 10

4x - 4x = 10 - 12

0 = -2 which is of course absurd so there is no solution to this equation.

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2 years ago

Read 2 more answers

What is −13+2z=−56 Thanks

Zinaida [17]

<h3>Original Equation:</h3>

$-\frac{1}{3}+2z=-\frac{5}{6}$

<h3>Steps:</h3>

<em>*To solve for a variable, isolate the desired variable onto one side.</em>

Firstly, we want to add 1/3 to each side however -5/6 and 1/3 do not share the same denominator, and we want them to have that and we can do that by finding the LCD, or lowest common denominator. To find the LCD, list the multiples of 6 and 3 and the lowest multiple that they share is their LCD. In this case, their LCD is 6. Multiply -1/3 by 2/2:

$-\frac{1}{3}\times \frac{2}{2}=-\frac{2}{6}\\\\-\frac{2}{6}+2z=-\frac{5}{6}$

Now that we have common denominators, add both sides by 2/6:

$2z=-\frac{3}{6}\\\\2z=-\frac{1}{2}$

Next, you want to cancel out 2 to isolate z. Usually, one would divide both sides by 2, however remember that <u>dividing by a number is the same as multiplying by it's reciprocal.</u> To find a number's reciprocal, flip the numerator and denominator around. In this case, since 2 is a <em>whole number</em> this means that the denominator is 1. In this case: 2/1 would become 1/2. Multiply both sides by 1/2:

$\frac{1}{2}\times 2z= -\frac{1}{2}\times \frac{1}{2}\\\\z=-\frac{1}{4}$

<h3>Final Answer:</h3>

<u>Your final answer is z = -1/4.</u>

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2 years ago

How do I simplify a fraction? For example if the question is 7 1/5 divided by 2 2/15 what would I do to simplify?

Westkost [7]

7 1/5:
Multiply the denominator and the whole number: 7*5 = 35 and then add the numerator: 35+1= 36/5. Then, do this for the following fraction, the improper fraction value of 2 2/15 is 32/15.
Now we need 36/5 & 32/15 to have common denominators so that we can simplify it a little less complicated.

For Instance,

36/5*3= 108/15

Now we divide, (108/15)/(32/15)
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Answer is 3 3/8.

Hope this was easy to understand!

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2 years ago

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Alex787 [66]

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3 years ago

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masha68 [24]

Answer:

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