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3 years ago

Help me Please!! Ive got a deadline!! Thanks! (:

Mathematics

1 answer:

saul85 [17]3 years ago

3 0

The equation in standard form is 2x^2 + 7x - 15=0. Factoring it gives you (2x-3)(x+5)= 0. That's the first one. The second one requires you to now your formula for the axis of symmetry which is x = -b/2a with a and b coming from your quadratic. Your a is -1 and your b is -2, so your axis of symmetry is
x= -(-2)/2(-1) which is x = 2/-2 which is x = -1. That -1 is the x coordinate of the vertex. You could plug that back into the equation and solve it for y, which is the easier way, or you could complete the square on the quadratic...let's plug in x to find y. -(-1)^2 - 2(-1)-1 = 0. So the vertex is (-1, 0). That's the first choice given. For the last one, since it is a negative quadratic it will be a mountain instead of a cup, meaning it doesn't open upwards, it opens downwards. Those quadratics will ALWAYS have a max value as opposed to a min value which occurs with an upwards opening parabola. This one is also the first choice because of the way the equation is written. There is no side to side movement (the lack of parenthesis tells us that) so the x coordinate for the vertex is 0. The -1 tells us that it has moved down from the origin 1 unit; hence the y coordinate is -1. The vertex is a max at (0, -1)

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aalyn [17]

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3 years ago

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Jlenok [28]

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3 years ago

Find mPRT. P 649U 42° R s

Mkey [24]

Answer: 296 degrees

Step-by-step explanation:

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So arc PRT = 360 degree - 64 degree = 296 degrees.

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2 years ago

A regular pentagon has an apothem of 7.3 inches and a perimeter of 53 inches. What is the area of the pentagon? Round your answe

zvonat [6]

Answer:

Area pf the regular pentagon is 193 $inch^{2}$ to the nearest whole number

Step-by-step explanation:

In this question, we are tasked with calculating the area of a regular pentagon, given the apothem and the perimeter

Mathematically, the area of a regular pentagon given the apothem and the perimeter can be calculated using the formula below;

Area of regular pentagon = 1/2 × apothem × perimeter

From the question, we can identify that the value of the apothem is 7.3 inches, while the value of the perimeter is 53 inches

We plug these values into the equation above to get;

Area = 1/2 × 7.3× 53 = 386.9/2 = 193.45 which is 193 $inch^{2}$ to the nearest whole number

3 0

3 years ago

Read 2 more answers

Sheila, janice, and katen, working together at the same rate, can complete a job in 3 1/3 days. Working at the same rate, how mu

pychu [463]

Answer:

Janice and Karen could do in 1 day:

20% of the job.

Step-by-step explanation:

To identify how much of the job could janice and caren do in 1 day, first, we must find how much of the job make just 1 person at the same rate:

If three persons make a job in 3 1/3 days, 1 person make the job in x:

3 persons ⇒ 3 1/3 days or 10/3 days
1 person ⇒ x

Then:

$x=\frac{1 person*\frac{10}{3}days }{3 persons}$ (we cancel the unit "persons")
$x=\frac{\frac{10}{3}days }{3}$
x = 10 days

Just a person would need 10 days to complete a job, now, we're gonna divide this value in 2 to obtain the time that need two persons to complete a job:

Time to complete a job between 2 persons = $\frac{10}{2}days$
Time to complete a job between 2 persons = 5 days

How two persons need 5 days to complete a job (in this case, the two persons are Janice and Karen), we can make a simple rule of three to obtain the percentage made in 1 day:

5 days ⇒ 100% of a job
1 day ⇒ x

Then:

$x=\frac{1*100}{5}$ (you can use the % if you want, the result is the same)
$x=\frac{100}{5}$
$x=20$

As you can see, Janice and Karen just in a day could do 20% of the job.

3 0

2 years ago