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3 years ago

Which of the following are solutions to the quadratic equation x squared plus 8x=9

Mathematics

1 answer:

Tanzania [10]3 years ago

5 0

Answer:

X=1 x=-9

Step-by-step explanation:

(x^2)+8x=9

(x^2)+8x-9=0

(x-1)(x+9)=0

x=1 x=-9

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The length of the base of a triangle is twice it’s height. If the area of the triangle is 441 square kilometers, find the height

Sonja [21]

Answer:

21 kilometers

Step-by-step explanation:

Let the height be $x$ . Then, the length of the base is $2x$ . The formula for the area is of the triangle is given by base*height/2. Therefore, the area of the triangle is equal to $\frac{x \cdot 2x}{2} = x^2$ , which is in turn equal to 441. Since $x$ must be positive, then $21^2=441$ , meaning that the height is $21$ kilometers.

5 0

3 years ago

So far this month John calculated that he will earn $40 in comission for his $500 in product sales. If John would like his comis

Helen [10]

John made $40 commissions for $500 sales or 40/500. He wants $320 for an unknown amount of sales or 320/x.

40/500=320/x Cross multiply.

40x=160,000

Divide both sides by 40.

X=4,000

He needs his sales to be $4,000 to get $320 in commission.

4 0

3 years ago

Find a number in the sequence<br><br> 1) 100, 400, 610, ?, 652<br><br> 2) 342, 128, ?, 26

dsp73

Answer:

1. 460

2. 216

Step-by-step explanation:

From the series ,

100 , 400 , 610 , ? , 652

Writing the the digits in the revere order , i.e

001 , 004 , 016 , ? , 256

Now,

Now , getting the number in the form of the multiple of 4 as -

1 , 1 * 4 = 4 , 4 * 4 = 16 , ? , 64 * 4 = 4

Hence , the value for ? = 16 * 4 = 64 .

Again , reversing 64 to get the missing number of the series -

460 .

Hence ,

The value for ? is 460 .

From the series ,

342 , 128 , ? , 26

Now, multiplying the first digit with the second digit and merging it to the product of the second and third digit -

3 * 4 and 4 * 2 , 1 * 2 and 2 * 8 , ?

128 , 216 , ?

Hence ,

The value for question mark = 1 * 2 and 1 * 6 = 216

Hence ,

The value for ? is 216 .

4 0

3 years ago

Form a polynomial function whose real zeros are in -1, 1, 3 and whose degree is 3

polet [3.4K]

The polynomial function whose real zeros are in -1, 1, 3 and whose degree is 3 is $x^3-3x^2-x+3=0$

Step-by-step explanation:

We need to find a polynomial function whose real zeros are in -1, 1, 3 and whose degree is 3.

If -1, 1 and 3 are real zeros, it can be written as:

x= -1, x= 1, and x = 3

or x+1=0, x-1=0 and x-3=0

Finding polynomial by multiply these factors:

$(x+1)(x-1)(x-3)=0\\(x+1)(x(x-3)-1(x-3))=0\\(x+1)(x^2-3x-x+3)=0\\(x+1)(x^2-4x+3)=0\\x(x^2-4x+3)+1(x^2-4x+3)=0\\x^3-4x^2+3x+x^2-4x+3=0\\Combining\,\,like\,\,terms:\\x^3-4x^2+x^2+3x-4x+3=0\\x^3-3x^2-x+3=0$

So, The polynomial function whose real zeros are in -1, 1, 3 and whose degree is 3 is $x^3-3x^2-x+3=0$

Keywords: Real zeros of Polynomials

Learn more about Real zeros of Polynomials at:

#learnwithBrainly

8 0

3 years ago

If 3t-7=5t, then 6t#

Inessa05 [86]

Here, 3t - 7 = 5t
5t - 3t = -7
2t = -7
t = -7/2

Then, 6t = 6(-7/2) = 3(-7) = -21

In short, Your Answer would be -21

Hope this helps!

3 0

3 years ago