Q20 y varies directly as the square of (x – 3). y= 16 when x=1. Find y when x= 10.

mojhsa [17]

8x-7x=-1+4
1x/1 =3/1
x=3

6 0

3 years ago

HIGH POINTS!!! Kevin will be painting a box that has a length of 10 cm, a width of 9cm and a height of 11 cm. How much paint wil

Vlad [161]

Answer:

990 square cm.

Step-by-step explanation:

To solve this problem, we simply multiply the length, the width, and the height. The formula is shown below:

$x=(l)(w)(h)$

l = length

w = width

h = height

Now, plug in the values:

$x=(10)(9)(11)$

$x=990$

Kevin will need 990 square cm. of paint to cover the box.

7 0

3 years ago

0.9(x+1.4)−2.3+0.1x=1.6

IgorC [24]

so what you do is distribute the 0.9 to x and 1.4 to get 0.9x+1.26 then combine like terms 1.9x - 1.04= 1.6 then add 1.04 to both sides to get 1.9x = 2.64 divide 1.9 to both sides

answer:1.389 and if you round 1.39

6 0

4 years ago

2. Ariana has created a paper airplane for her physics class at school where all the students will be testing their planes by se

sergiy2304 [10]

Answer:

2. The airplane will crash into the ground after 5 seconds.

3. The domain of the function is [0,30] and range of the function is $[-\infty,900]$ .

Step-by-step explanation:

2.

Ariana initial attempt is modeled by the function,

$h(x)=x^2-12x+35$

where, h is the height in feet and x is the time in seconds of the paper airplanes path.

If airplane crash into the ground, then $h(x)=0$ ,

$0=x^2-12x+35$

$0=x^2-7x-5x+35$

$0=x(x-7)-5(x-7)$

$0=(x-7)(x-5)$

Equate each factor equal to 0.

$x=5,7$

Therefore the airplane will crash into the ground after 5 seconds.

3.

The height of the rocket in meters is modeled by the function shown below, where t is time in seconds.

$h(t)=-4t^2+120t$

The value of t must be positive because time can not be negative.

Find the zeros of the function.

$0=-4t(t-30)$

$t=0,30$

The leading coefficient is negative, so the it is a downward parabola. Since the zeros of the function are 0 and 30, therefore the function is negative before 0 and after 30.

The height can not be negative, so the domain of the function is

$0\leq t\leq 30$