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2 years ago

The function f(x) varies directly with x and f(x)=160 when x=40.

Mathematics

1 answer:

DaniilM [7]2 years ago

4 0

160÷40 is 4 so i think the function f multiplies x by 4.
when x is 8, 8×4=32 so the answer shld be 32

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Find the earnings rounded to the nearest cent <br>sales: $984 <br>commission: 10%

Scilla [17]

Answer:

$1082

Step-by-step explanation:

10% of $984

10/100 ($984)= $98.4

Earnings = ($98.4+$984)

Earnings = $1082.4

Earnings = $1082 (to the nearest cent)

6 0

2 years ago

Find the general solution of the following ODE: y' + 1/t y = 3 cos(2t), t > 0.

Margarita [4]

Answer:

y = 3sin2t/2 - 3cos2t/4t + C/t

Step-by-step explanation:

The differential equation y' + 1/t y = 3 cos(2t) is a first order differential equation in the form y'+p(t)y = q(t) with integrating factor I = e^∫p(t)dt

Comparing the standard form with the given differential equation.

p(t) = 1/t and q(t) = 3cos(2t)

I = e^∫1/tdt

I = e^ln(t)

I = t

The general solution for first a first order DE is expressed as;

y×I = ∫q(t)Idt + C where I is the integrating factor and C is the constant of integration.

yt = ∫t(3cos2t)dt

yt = 3∫t(cos2t)dt ...... 1

Integrating ∫t(cos2t)dt using integration by part.

Let u = t, dv = cos2tdt

du/dt = 1; du = dt

v = ∫(cos2t)dt

v = sin2t/2

∫t(cos2t)dt = t(sin2t/2) + ∫(sin2t)/2dt

= tsin2t/2 - cos2t/4 ..... 2

Substituting equation 2 into 1

yt = 3(tsin2t/2 - cos2t/4) + C

Divide through by t

y = 3sin2t/2 - 3cos2t/4t + C/t

Hence the general solution to the ODE is y = 3sin2t/2 - 3cos2t/4t + C/t

3 0

3 years ago

The general form of an parabola is 2x2−12x−3y+12=0 .

Murljashka [212]

Answer:

The standard form of the parabola is $(x-3)^2=4*\frac{3}{8}(y+2)$

Step-by-step explanation:

The standard form of a parabola is

$(x-h)^2=4p(y-k)$ .

In order to convert $2x^2-12x-3y+12=0$ into the standard form, we first separate the variables:

$2x^2-12x+3y+12=0\\\\2x^2-12x+12=3y$

we now divided both sides by 2 to remove the coefficient from $2x^2$ and get:

$x^2-6x+6=\frac{3}{2}y$ .

We complete the square on the left side by adding 3 to both sides:

$x^2-6x+6+3=\frac{3}{2}y+3$

$x^2-6x+9=\frac{3}{2}y+3$

$(x-3)^2=\frac{3}{2}y+3$

now we bring the right side into the form $4p(y-k)$ by first multiplying the equation by $\frac{2}{3}$ :

$\frac{2}{3} *(x-3)^2=\frac{2}{3} *(\frac{3}{2}y+3)\\\\\frac{2}{3} *(x-3)^2=y+2$

and then we multiplying both sides by $\frac{3}{2}$ to get

$(x-3)^2=\frac{3}{2} (y+2)$ .

Here we see that

$4p=\frac{3}{2}$

$\therefore p=\frac{3}{8}$

Thus, finally we have the equation of the parabola in the standard form:

$\boxed{(x-3)^2=4*\frac{3}{8}(y+2)}$

5 0

2 years ago

Sam earns $12.50 an hour cleaning houses. If he works from 8:00am to 5:00pm,

Mumz [18]

8-5 is 9 hours
9hrs x 12.50 = $112.5

5 0

2 years ago

Read 2 more answers

There is a 60% chance that your math teacher will give a pop quiz tonight, and due to the fact that you have a soccer game, ther

s2008m [1.1K]

Probability of Quiz = 0.6
Probability of Not doing homework 0.85

Probability of both event happening = P1 * P2 = 0.51

The probability of there being a quiz and you not doing the homework is 51%

6 0

2 years ago