Find the area of polygon

kolezko [41]

257 1/2 should be the correct answer

4 0

3 years ago

You buy the same number of brushes, rollers and paint cans. Write an expression in simples form that represents the total amount

jeyben [28]

T= 21.79x + 3.99x + 6.89x where t is the total cost and x is the number of brushes/rollers/paint cans you buy. You don't need a different variable for each item because you buy the same amount of each.

4 0

3 years ago

Read 2 more answers

50 POINTS! QUICKLY Are the pairs of variables x and y the solutions to the equation x^2–2y=7?

Fittoniya [83]

Hi there!

$\large\boxed{(5,8) \text{ and } (1.2, -2.78)}}$

We are given the equation:

x² - 2y = 7

To verify if each ordered pair is apart of the function, we can plug in their respective x and y values:

1. (5)² - 2(8) = 7

25 - 16 = 9 ≠ 7. This is NOT correct.

2. (-1)² - 2(-3) = 7

1 + 6 = 7. This is correct.

3. (-4)² - 2(-11.5) = 7

16 + 23 = 39 ≠ 7. This is NOT correct.

4. (1.2)² - 2(-2.78) = 7

1.44 +5.56 = 7. This is correct.

Thus, only 1 and 4 are the correct answers.

5 0

3 years ago

Read 2 more answers

If the sum of the zereos of the quadratic polynomial is 3x^2-(3k-2)x-(k-6) is equal to the product of the zereos, then find k?

lys-0071 [83]

Answer:

2

Step-by-step explanation:

So I'm going to use vieta's formula.

Let u and v the zeros of the given quadratic in ax^2+bx+c form.

By vieta's formula:

1) u+v=-b/a

2) uv=c/a

We are also given not by the formula but by this problem:

3) u+v=uv

If we plug 1) and 2) into 3) we get:

-b/a=c/a

Multiply both sides by a:

-b=c

Here we have:

a=3

b=-(3k-2)

c=-(k-6)

So we are solving

-b=c for k:

3k-2=-(k-6)

Distribute:

3k-2=-k+6

Add k on both sides:

4k-2=6

Add 2 on both side:

4k=8

Divide both sides by 4:

k=2

Let's check:

$3x^2-(3k-2)x-(k-6) \text{ with }k=2$ :

$3x^2-(3\cdot 2-2)x-(2-6)$

$3x^2-4x+4$

I'm going to solve $3x^2-4x+4=0$ for x using the quadratic formula:

$\frac{-b\pm \sqrt{b^2-4ac}}{2a}$

$\frac{4\pm \sqrt{(-4)^2-4(3)(4)}}{2(3)}$

$\frac{4\pm \sqrt{16-16(3)}}{6}$

$\frac{4\pm \sqrt{16}\sqrt{1-(3)}}{6}$

$\frac{4\pm 4\sqrt{-2}}{6}$

$\frac{2\pm 2\sqrt{-2}}{3}$

$\frac{2\pm 2i\sqrt{2}}{3}$

Let's see if uv=u+v holds.

$uv=\frac{2+2i\sqrt{2}}{3} \cdot \frac{2-2i\sqrt{2}}{3}$

Keep in mind you are multiplying conjugates:

$uv=\frac{1}{9}(4-4i^2(2))$

$uv=\frac{1}{9}(4+4(2))$

$uv=\frac{12}{9}=\frac{4}{3}$

Let's see what u+v is now:

$u+v=\frac{2+2i\sqrt{2}}{3}+\frac{2-2i\sqrt{2}}{3}$

$u+v=\frac{2}{3}+\frac{2}{3}=\frac{4}{3}$

We have confirmed uv=u+v for k=2.

4 0

3 years ago

Otis plans to make 3 batches of sidewalk chalk How much plaster of paris does he need

den301095 [7]

Answer:

$4\frac{1}{2}$ cups plaster of paris.

Step-by-step explanation:

Given:

for one batch of sidewalk chalk = $1\frac{1}{2}$ cup plaster of paris.

Number of bathes = 3

We need to find quantity of plaster of paris.

Solution:

For making 1 batch of sidewalk chalk = $1\frac{1}{2}$ cup plaster of paris.

For making 3 batches of sidewalk chalk = $3\times 1\frac{1}{2}$ cup plaster of paris.

$= 3\times \frac{2\times 1+1}{2}$

$= 3\times \frac{2+1}{2}$

$= 3\times \frac{3}{2}$

$= \frac{3\times 3}{2}$

$= \frac{9}{2}$

$=4\frac{1}{2}$

Therefore, he needed $4\frac{1}{2}$ cups plaster of paris.

5 0

4 years ago