Which of the following constants can be added to x2 - 10x to form a perfect square trinomial?

Denelle is decorating a ballroom ceiling with garland. If the rectangular ceiling is 63 feet by 60 feet, how much garland will D

AURORKA [14]

Answer:

The answer to your question is: 3780 m²

Step-by-step explanation:

Data

Rectangular ceiling

base = 63 ft

height = 60 ft

Formula

Area = base x height

Process

Area = 63 x 60

= 3780 m²

7 0

3 years ago

Whats 3(x + 2) = 21?<br>show work please !!

dybincka [34]

Answer:

x=5

Step-by-step explanation:

$3(x+2)=21$

$3x+6=21$

$3x+6-6=21-6\\\\3x=15\\\\\frac{3x}{3} = \frac{15}{3} \\\\x=5$

5 0

3 years ago

Read 2 more answers

Suppose cos(x)= -1/3, where π/2 ≤ x ≤ π. What is the value of tan(2x). EDGE

AVprozaik [17]

Answer:

D

Step-by-step explanation:

We are given that:

$\displaystyle \cos x = -\frac{1}{3}\text{ where } \pi /2 \leq x \leq \pi$

And we want to find the value of tan(2<em>x</em>).

Note that since <em>x</em> is between π/2 and π, it is in QII.

In QII, cosine and tangent are negative and only sine is positive.

We can rewrite our expression as:

$\displaystyle \tan(2x)=\frac{\sin(2x)}{\cos(2x)}$

Using double angle identities:

$\displaystyle \tan(2x)=\frac{2\sin x\cos x}{\cos^2 x-\sin^2 x}$

Since cosine relates the ratio of the adjacent side to the hypotenuse and we are given that cos(<em>x</em>) = -1/3, this means that our adjacent side is one and our hypotenuse is three (we can ignore the negative). Using this information, find the opposite side:

$\displaystyle o=\sqrt{3^2-1^2}=\sqrt{8}=2\sqrt{2}$

So, our adjacent side is 1, our opposite side is 2√2, and our hypotenuse is 3.

From the above information, substitute in appropriate values. And since <em>x</em> is in QII, cosine and tangent will be negative while sine will be positive. Hence:

<h2> $\displaystyle \tan(2x)=\frac{2(2\sqrt{2}/3)(-1/3)}{(-1/3)^2-(2\sqrt{2}/3)^2}$ </h2>

Simplify:

$\displaystyle \tan(2x)=\frac{-4\sqrt{2}/9}{(1/9)-(8/9)}$

Evaluate:

$\displaystyle \tan(2x)=\frac{-4\sqrt{2}/9}{-7/9} = \frac{4\sqrt{2}}{7}$

The final answer is positive, so we can eliminate A and B.

We can simplify D to:

$\displaystyle \frac{2\sqrt{8}}{7}=\frac{2(2\sqrt{2}}{7}=\frac{4\sqrt{2}}{7}$

So, our answer is D.

7 0

3 years ago

(1 point) A particle starts at the point P=(−2,−1,3)P=(−2,−1,3) when t=0t=0 and moves along a straight line toward Q=(−4,0,6)Q=(

Ahat [919]

Answer:

The position is given by r(t) = (-2 -t √14, 1 + √3.5, 3 + 3√3.5)

Step-by-step explanation:

The direction is given by the difference between the starting point and the end point, thus it is (-4,0,6)-(-2,-1,3) = (-2,1,3). The norm of this vector is √( (-2)²+1²+3²) = √14 = 3.7416 secons

Since the speed is 7 cm/sec, we need to multiply this vector by 7/√14 = √3.5 in order to obtain how much does the particle advance each second.

As a consecuence, it advances (-2,1,3) * √3.5 = (- √14, √3.5, 3 √3.5)

And, as a result, the position after t seconds is given by the function

r(t) = (-2,1,3) + t (-√14, √3.5, 3 √3.5) = (-2 -t √14, 1 + √3.5, 3 + 3√3.5)

8 0

3 years ago

The work of a student to find the dimensions of a rectangle of area 6 + 8x and width 2 is shown below:

tatiyna

Answer:
Step 2; 2(3) = 2(4x)

5 0

3 years ago

Read 2 more answers