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4 years ago

Complete the steps for solving 7 = –2x2 + 10x.

Mathematics

2 answers:

Nikitich [7]4 years ago

4 0

Answer:

1. -2

2. add 25/4

3. sub 25/2

4. 5/2

Step-by-step explanation:

Whitepunk [10]4 years ago

4 0

Answer:

1. -2

2. add 25/4

3. sub 25/2

4. 5/2

Step-by-step explanation:

You might be interested in

The ratio of girls to boys is 4:5 if there are 27 total students how many are girls? Boys?

kompoz [17]

4/9 x 27 = girls
12 girls

5/9 x 27 = boys
15boys

4 0

3 years ago

Evaluate the surface integral S F · dS for the given vector field F and the oriented surface S.

sweet-ann [11.9K]

Answer:

2.794

Step-by-step explanation:

Recall that if G(x,y) is a parametrization of the surface S and F and G are smooth enough then

$\bf \displaystyle\iint_{S}FdS=\displaystyle\iint_{R}F(G(x,y))\cdot(\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y})dxdy$

F can be written as

F(x,y,z) = (xy, yz, zx)

and S has a straightforward parametrization as

$\bf G(x,y) = (x, y, 3-x^2-y^2)$

with 0≤ x≤1 and 0≤ y≤1

$\bf \displaystyle\frac{\partial G}{\partial x}= (1,0,-2x)\\\\\displaystyle\frac{\partial G}{\partial y}= (0,1,-2y)\\\\\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y}=(2x,2y,1)$

we also have

$\bf F(G(x,y))=F(x, y, 3-x^2-y^2)=(xy,y(3-x^2-y^2),x(3-x^2-y^2))=\\\\=(xy,3y-x^2y-y^3,3x-x^3-xy^2)$

and so

$\bf F(G(x,y))\cdot(\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y})=(xy,3y-x^2y-y^3,3x-x^3-xy^2)\cdot(2x,2y,1)=\\\\=2x^2y+6y^2-2x^2y^2-2y^4+3x-x^3-xy^2$

we just have then to compute a double integral of a polynomial on the unit square 0≤ x≤1 and 0≤ y≤1

$\bf \displaystyle\int_{0}^{1}\displaystyle\int_{0}^{1}(2x^2y+6y^2-2x^2y^2-2y^4+3x-x^3-xy^2)dxdy=\\\\=2\displaystyle\int_{0}^{1}x^2dx\displaystyle\int_{0}^{1}ydy+6\displaystyle\int_{0}^{1}dx\displaystyle\int_{0}^{1}y^2dy-2\displaystyle\int_{0}^{1}x^2dx\displaystyle\int_{0}^{1}y^2dy-2\displaystyle\int_{0}^{1}dx\displaystyle\int_{0}^{1}y^4dy+\\\\+3\displaystyle\int_{0}^{1}xdx\displaystyle\int_{0}^{1}dy-\displaystyle\int_{0}^{1}x^3dx\displaystyle\int_{0}^{1}dy-\displaystyle\int_{0}^{1}xdx\displaystyle\int_{0}^{1}y^2dy$

=1/3+2-2/9-2/5+3/2-1/4-1/6 = 2.794

5 0

3 years ago

You want to order carpet for an area in your house. The room measures 12 feet by 10 feet. Remember, Area = Length × Width. If ea

pochemuha

Answer:

402.9 $

Step-by-step explanation:

first you must turn foot into yards "every 3 foot = 1 yard"

3.33 , 4

then we will use the area=length x width formula

3.33 x 4 = 13.32 square yards

the cost of the carpet is

13.32 x 30.25 = 402.9$

4 0

4 years ago

Estimate how much farther sound travels through stone in 17 seconds than through a aluminum in the same time

aev [14]

Sound travels 10200m farther through stone in 17 seconds than through aluminium

Speed of sound in aluminium = 3100 m/s

The speed of sound in stone = 3700 m/s

Time taken = 17 minutes

Distance traveled = Speed x Time

Distance traveled by sound in aluminium in 17 seconds = 3100 x 17

Distance traveled by sound in aluminium in 17 seconds = 52700 m

Distance traveled by sound in stone in 17 seconds = 3700 x 17

Distance traveled by sound in stone in 17 seconds = 62900 m

Difference in the distance traveled = 62900 - 52700

Difference in the distance traveled = 10200 m

Sound travels 10200m farther through stone in 17 seconds than through aluminium

Learn more here: brainly.com/question/13096122

6 0

3 years ago

Janice made 1/3 of a quart of hot chocolate. Each mug holds 1/6 of a quart. How many mugs will Janice be able to fill?

Sloan [31]

She will be able to fill 2 mugs

3 0

3 years ago