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3 years ago

BRAINLIEST!URGENT! Please help if you can. If you know the answer, please leave an explanation and I will mark you brainliest!

Mathematics

1 answer:

Dafna1 [17]3 years ago

7 0

The vertex form of a quadratic equation is y = n(x − h)2 + k, where (h, k) gives the coordinates of the vertex of the parabola in the xy-plane and the sign of the constant n determines whether the parabola opens upward or downward.

If n is negative, the parabola opens downward and the vertex is the maximum.

The given equation has the values h = 3, k = a, and n = −1.

Therefore, the vertex of the parabola is (3, a) and the parabola opens downward.

Thus, the parabola’s maximum occurs at (3, a)

Ans D

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Mary made 1/5 of a batch of cookies in 1/10th of an hour, how many batches of cookies can she make in one hour? This is unit rat

barxatty [35]

Answer:

1/5 ÷ 1/10 = 10/5

Step-by-step explanation:

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3 years ago

4y-7x=16 solve for y

kompoz [17]

I think the answer would be x= 4/7 y = +-16/7

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3 years ago

Read 2 more answers

The athletic departments at 10 randomly selected U.S. universities were asked by the Equal Employment Opportunity Commission to

Lesechka [4]

Answer: Mean = 3.5 , median = 2.5, mode = 2, geometric mean = 2.74

Median is the most appropriate measure of central tendency.

The least appropriate = mean

Yes there is an outlier.

Step-by-step explanation:

Given responses : 5, 4, 2, 1, 1, 2, 10, 2, 3, 5.

First arrange them in increasing order, $\sqrt[10]{1\times1\times2\times2\times2\times3\times4\times5\times5\times10 }\\\\=\sqrt[10]{24000} \approx2.74$

Its sum = 35

Mean of n observations = (Sum of observations) ÷ n

Mean = (35) ÷ 10

=3.5

Here n =10 (even)

Median = average of middle most numbers = $\dfrac{2+3}{2}=\dfrac52=2.5$

Mode = most repeated number = 2 (thrice)

geometric mean = $\sqrt[n]{x_1\times x_2\times.... x_n}$

10 is an outlier as it is very large as compare to other numbers.

When outlier is present in data , the median is the most appropriate measure of central tendency.

Mean affected badly by the outlier so it the least appropriate.

4 0

3 years ago

You work at a pioneer historical site. On this site you have handcarts. One cart has a handle that connects to the center of the

Gelneren [198K]

Answer:

a) see below

b) radius = 16.4 in (1 d.p.)

c) 18°. Yes contents will remain. No, handle will not rest on the ground.

d) Yes contents would spill. Max height of handle = 32.8 in (1 d.p.)

Step-by-step explanation:

Part a

A chord is a line segment with endpoints on the circumference of the circle.

The diameter is a chord that passes through the center of a circle.

Therefore, the spokes passing through the center of the wheel are congruent chords.

The spokes on the wheel represent the radii of the circle. Spokes on a wheel are usually evenly spaced, therefore the congruent central angles are the angles formed when two spokes meet at the center of the wheel.

Part b

The tangent of a circle is always perpendicular to the radius.

The tangent to the wheel touches the wheel at point B on the diagram. The radius is at a right angle to this tangent. Therefore, we can model this as a right triangle and use the tan trigonometric ratio to calculate the radius of the wheel (see attached diagram 1).

$\sf \tan(\theta)=\dfrac{O}{A}$

where:

$\theta$ is the angle
O is the side opposite the angle
A is the side adjacent the angle

Given:

$\theta$ = 20°
O = radius (r)
A = 45 in

Substituting the given values into the tan trig ratio:

$\implies \sf \tan(20^{\circ})=\dfrac{r}{45}$

$\implies \sf r=45\tan(20^{\circ})$

$\implies \sf r=16.37866054...$

Therefore, the radius is 16.4 in (1 d.p.).

Part c

The measure of an angle formed by a secant and a tangent from a point outside the circle is half the difference of the measures of the intercepted arcs.

If the measure of the arc AB was changed to 72°, then the other intercepted arc would be 180° - 72° = 108° (since AC is the diameter).

$\implies \sf new\: angle=\dfrac{108^{\circ}-72^{\circ}}{2}=18^{\circ}$

As the handle of the cart needs to be no more than 20° with the ground for the contents not to spill out, the contents will remain in the handcart at an angle of 18°.

The handle will not rest of the ground (see attached diagram 2).

Part d

This can be modeled as a right triangle (see diagram 3), with:

height = (48 - r) in
hypotenuse ≈ 48 in

Use the sin trig ratio to find the angle the handle makes with the horizontal:

$\implies \sf \sin (\theta)=\dfrac{O}{H}$

$\implies \sf \sin (\theta)=\dfrac{48-r}{48}$

$\implies \sf \sin (\theta)=\dfrac{48-45\tan(20^{\circ})}{48}$

$\implies \theta = 41.2^{\circ}\:\sf(1\:d.p.)$

As 41.2° > 20° the contents will spill out the back.

To find the maximum height of the handle from the ground before the contents start spilling out, find the height from center of the wheel (setting the angle to its maximum of 20°):

$\implies \sin(20^{\circ})=\dfrac{h}{48}$

$\implies h=48\sin(20^{\circ})$

Then add it to the radius:

$\implies \sf max\:height=48\sin(20^{\circ})+45\tan(20^{\circ})=32.8\:in\:(1\:d.p.)$

(see diagram 4)

------------------------------------------------------------------------------------------

Circle Theorem vocabulary

Secant: a straight line that intersects a circle at two points.

Arc: the curve between two points on the circumference of a circle

Intercepted arc: the curve between the two points where two chords or line segments (that meet at one point on the other side of the circle) intercept the circumference of a circle.

Tangent: a straight line that touches a circle at only one point.

7 0

2 years ago

While mining Fred found a large metal bar that contained 24 ounces of nickel. Fred also determined that the bar was 80% nickel.

frutty [35]

Answer:

Not that I'm a chemistry expert but mathematically,The total weight of the bar is directly proportional to the known weight of the bar and the given percentage. I worked it out and found that the the total weight of the bar is 30 ounces. This is how I did it

Step-by-step explanation:

80:24

100:n

80(n)=100×24

A little equation and after it's solve the variable (n) will be equal to 30

The unit is added after calculations so that's how the answer is 30 ounces

8 0

3 years ago

BRAINLIEST!URGENT! Please help if you can. If you know the answer, please leave an explanation and I will mark you brainliest!​

BRAINLIEST!URGENT! Please help if you can. If you know the answer, please leave an explanation and I will mark you brainliest!