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3 years ago

Express the area of the triangle shown below in terms of b and θ only.

1 answer:

8 0

Given a right triangle with base, b and height, h with the angle opposide side h as θ.

The area of a triangle is given by
$A= \frac{1}{2} bh$

But,
$\tan\theta= \frac{h}{b} \\ \\ \Rightarrow h=b\tan\theta$

Therefore, the area of the triangle in terms of <span>b and θ only is given by
$A= \frac{1}{2} b(b\tan\theta)= \frac{1}{2} b^2\tan\theta$ </span>

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Every autumn, the North American Monarch

Stolb23 [73]

Part A

The equation is d = 50t

This is because the slope of 50 represents how many miles per day the butterflies cover (on average). The y intercept is 0 to indicate that 0 miles have been traveled initially.

You can think of this as the equation y = 50x

If t = 1, then d = 50t = 50*1 = 50 miles have been covered

If t = 2, then d = 50t = 50*2 = 100 miles have been covered

And so on.

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Part B

You'll have these values in the bottom row (in the order presented): 50, 100, 150, 200, 250

You can plug in the values t = 1, t = 2, t = 3, t = 4 and t = 5 into d = 50t to find those answers in bold.

Or you could add on 50 each time to generate each new value. We start at 50 since t = 1 corresponds to d = 50.

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Part C

You can keep the pattern of 50,100,150, ... going until you reach 2500. Then note the t value that pairs with d = 2500

In my opinion, that's the slower method.

The quicker method is to plug d = 2500 into the equation for part A, and then solve for t.

d = 50t

2500 = 50t

50t = 2500

50t/50 = 2500/50 ....... divide both sides by 50

t = 50

It will take 50 days for the average distance traveled to be 2500 miles.

6 0

3 years ago

EMERGENCY HELP! A steady stream of water flows into a partially-filled rectangular tank. After 6 minutes, there are 87 gallons o

german

Answer:

$y=9x+33$

33 gallons of water to begin with.

Step-by-step explanation:

So we essentially are given two coordinates: (6,87) and (21,222). To find an equation, we simply need to find the slope and y-intercept. We know it's a linear equation because it's a steady stream, meaning a constant slope.

The slope is:

$m=\frac{y_2-y_1}{x_2-x_1}=\frac{222-87}{21-6}=135/15=9$

So, the rate at which the stream flows is 9 gallons per minute.

Now, let's find the initial amount of water. To do this, we can use point-slope form. Pick either of the two points. I'm going to use (6,87).

$y-y_1=m(x-x_1)\\y-87=9(x-6)\\y-87=19-54\\y=9x+33$

So, there were 33 gallons of water in the tank to begin with.

3 0

3 years ago

Can somebody help me find the perimeter of this figure?

lbvjy [14]

Answer: P = 64in,

Step-by-step explanation: P = 17 + 13 + 25 + 9

3 0

3 years ago

A box designer has been charged with the task of determining the surface area of various open boxes (no lid) that can be constru

Viktor [21]

Answer:

1) $S = 2\cdot w\cdot l - 8\cdot x^{2}$ , 2) The domain of S is $0 \leq x \leq \frac{\sqrt{w\cdot l}}{2}$ . The range of S is $0 \leq S \leq 2\cdot w \cdot l$ , 3) $S = 176\,in^{2}$ , 4) $x \approx 4.528\,in$ , 5) $S = 164.830\,in^{2}$

Step-by-step explanation:

1) The function of the box is:

$S = 2\cdot (w - 2\cdot x)\cdot x + 2\cdot (l-2\cdot x)\cdot x +(w-2\cdot x)\cdot (l-2\cdot x)$

$S = 2\cdot w\cdot x - 4\cdot x^{2} + 2\cdot l\cdot x - 4\cdot x^{2} + w\cdot l -2\cdot (l + w)\cdot x + l\cdot w$

$S = 2\cdot (w+l)\cdot x - 8\cdpt x^{2} + 2\cdot w \cdot l - 2\cdot (l+w)\cdot x$

$S = 2\cdot w\cdot l - 8\cdot x^{2}$

2) The maximum cutout is:

$2\cdot w \cdot l - 8\cdot x^{2} = 0$

$w\cdot l - 4\cdot x^{2} = 0$

$4\cdot x^{2} = w\cdot l$

$x = \frac{\sqrt{w\cdot l}}{2}$

The domain of S is $0 \leq x \leq \frac{\sqrt{w\cdot l}}{2}$ . The range of S is $0 \leq S \leq 2\cdot w \cdot l$

3) The surface area when a 1'' x 1'' square is cut out is:

$S = 2\cdot (8\,in)\cdot (11.5\,in)-8\cdot (1\,in)^{2}$

$S = 176\,in^{2}$

4) The size is found by solving the following second-order polynomial:

$20\,in^{2} = 2 \cdot (8\,in)\cdot (11.5\,in)-8\cdot x^{2}$

$20\,in^{2} = 184\,in^{2} - 8\cdot x^{2}$

$8\cdot x^{2} - 164\,in^{2} = 0$

$x \approx 4.528\,in$

5) The equation of the box volume is:

$V = (w-2\cdot x)\cdot (l-2\cdot x) \cdot x$

$V = [w\cdot l -2\cdot (w+l)\cdot x + 4\cdot x^{2}]\cdot x$

$V = w\cdot l \cdot x - 2\cdot (w+l)\cdot x^{2} + 4\cdot x^{3}$

$V = (8\,in)\cdot (11.5\,in)\cdot x - 2\cdot (19.5\,in)\cdot x^{2} + 4\cdot x^{3}$

$V = (92\,in^{2})\cdot x - (39\,in)\cdot x^{2} + 4\cdot x^{3}$

The first derivative of the function is:

$V' = 92\,in^{2} - (78\,in)\cdot x + 12\cdot x^{2}$

The critical points are determined by equalizing the derivative to zero:

$12\cdot x^{2}-(78\,in)\cdot x + 92\,in^{2} = 0$

$x_{1} \approx 4.952\,in$

$x_{2}\approx 1.548\,in$

The second derivative is found afterwards:

$V'' = 24\cdot x - 78\,in$

After evaluating each critical point, it follows that $x_{1}$ is an absolute minimum and $x_{2}$ is an absolute maximum. Hence, the value of the cutoff so that volume is maximized is:

$x \approx 1.548\,in$

The surface area of the box is:

$S = 2\cdot (8\,in)\cdot (11.5\,in)-8\cdot (1.548\,in)^{2}$

$S = 164.830\,in^{2}$

4 0

3 years ago

I need help ASAP please

Fiesta28 [93]

Answer:

B. 20 feet

Step-by-step explanation:

<u>If the triangles are similar that means the ratio of the sides of the triangles are the same.</u>

Sense the left side of bigger triangle is 4 times bigger than the bottom side of the triangle, then the left side of the smaller triangle is 4 times bigger than the bottom side.

5×4=20

7 0

2 years ago