All categories

3 years ago

Find an integer value of b that makes x^2 + bx - 81 factorable

Mathematics

1 answer:

m_a_m_a [10]3 years ago

3 0

x² + bx - 81

there are 2 formula that fit this equation :

>> x² - a² = (x+a)(x-a)

>> x² + 2ax² + a² = (x+a)(x+a)

because the last value of our equation is negative value therefore we have to use the first formula >> x² - a² = (x+a)(x-a)

step:

x² + bx - 81

x² + bx - 9²

because we have to follow the first formula x² - a² therefore bx = 0

x² + bx - 9²

bx = 0

b = 0

You might be interested in

. A high-speed maglev train in Shanghai can

tresset_1 [31]

The speed of Maglev train is 267 miles per hour.

Step-by-step explanation:

Given,

Speed of Maglev train = 430 kilometers per hour

We know that;

1 kilometer = 0.62 miles

Therefore,

430 kilometers = 0.62*430

430 kilometers = 266.6 miles

Rounding off to nearest whole number

430 kilometers = 267 miles

The speed of Maglev train is 267 miles per hour.

Keywords: Speed, conversion

Learn more about conversion at:

#LearnwithBrainly

5 0

3 years ago

Question 5 (2) x cube - 3x square 9x - 5

kakasveta [241]

Please, post the instructions along with your question, and if possible share the question in symbolic form, not in words.

Do you mean Question #5? By (2) x cube, do you mean 2x^3?

I strongly suggest that you use lots of parentheses ( ) to show how your numbers are grouped, and not to use " x " to denote multiplication (use " * " for that, please.

If only you'll clear this up, I'd be happy to help.

I will assume that your post is 2x^3 - 3(9x-5)^2.

Then 2x^3 - 3(81x - 90x + 25). Does this have any resemblance to what you wanted me to see in your post?

3 0

3 years ago

How do I solve this and what is the answer

expeople1 [14]

(-3) - (-3) = - 6
3 + (-3) = 0

4 0

3 years ago

Please help, WILL GIVE BRAINLIST

Arada [10]

Answer:

I would say B

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

After breaking your penny bank, you notice that you have $4.87 in quarters ($0.25), dimes ($0.10), nickels ($0.05), and pennies

ira [324]

Answer: Option 'c' is correct.

Step-by-step explanation:

Let the number of dimes be 'x'.

Let the number of nickels be ' $\dfrac{3}{2}x$ '.

Let the number of pennies be $\dfrac{3}{2}\times 2x=3x$

Let the number of quarters be '3x-34'.

As we know that

1 quarter = $0.25

1 dime = $0.10

1 nickel = $0.05

1 penny = $0.01

According to question, we get that

$0.10x+0.05\times \dfrac{3x}{2}+0.01\times 3x+0.25(3x-34)=4.87\\\\0.10x+0.075x+0.03x+0.75x-8.5=4.87\\\\\\0.955x=4.87+8.5\\\\0.955x=13.37\\\\x=\dfrac{13.37}{0.955}\\\\x=14$

So, the number of pennies is given by

$3x=3\times 14=42$

Hence, Option 'c' is correct.

3 0

2 years ago

Find an integer value of b that makes x^2 + bx - 81 factorable​

Find an integer value of b that makes x^2 + bx - 81 factorable