On Monday, ALL the Grade 7 students either bought their lunch at the canteen or brought their lunch from home. Given that 20% of the students bought their lunch at the canteen and 116 students brought lunch from home, how many students are in Grade 7?

Answer:

No answer is possible

Step-by-step explanation:

First, we can identify what the parabola looks like.

A parabola of form ax²+bx+c opens upward if a > 0 and downward if a < 0. The a is what the x² is multiplied by, and in this case, it is positive 2. Therefore, this parabola opens upward.

Next, the vertex of a parabola is equal to -b/(2a). Here, b (what x is multiplied by) is 1 and a =2, so -b/(2a) = -1/4 = -0.25.

This means that the parabola opens upward, and is going down until it reaches the vertex of x=-0.25 and up after that point. Graphing the function confirms this.

Given these, we can then solve for when the endpoints of the interval are reached and go from there.

The first endpoint in -2 ≤ f(x) ≤ 16 is f(x) = 2. Therefore, we can solve for f(x)=-2 by saying

2x²+x-4 = -2

add 2 to both sides to put everything on one side into a quadratic formula

2x²+x-2 = 0

To factor this, we first can identify, in ax²+bx+c, that a=2, b=1, and c=-2. We must find two values that add up to b=1 and multiply to c*a = -2  * 2 = -4. As (2,-2), (4,-1), and (-1,4) are the only integer values that multiply to -4, this will not work. We must apply the quadratic formula, so

x= (-b ± √(b²-4ac))/(2a)

x = (-1 ± √(1-(-4*2*2)))/(2*2)

= (-1 ± √(1+16))/4

= (-1 ± √17) / 4

when f(x) = -2

Next, we can solve for when f(x) = 16

2x²+x-4 = 16

subtract 16 from both sides to make this a quadratic equation

2x²+x-20 = 0

To factor, we must find two values that multiply to -40 and add up to 1. Nothing seems to work here in terms of whole numbers, so we can apply the quadratic formula, so

x = (-1 ± √(1-(-20*2*4)))/(2*2)

= (-1 ± √(1+160))/4

= (-1 ± √161)/4

Our two values of f(x) = -2 are (-1 ± √17) / 4 and our two values of f(x) = 16 are (-1 ± √161)/4 . Our vertex is at x=-0.25, so all values less than that are going down and all values greater than that are going up. We can notice that

(-1 - √17)/4 ≈ -1.3 and (-1-√161)/4 ≈ -3.4 are less than that value, while (-1+√17)/4 ≈ 0.8 and (-1+√161)/4 ≈ 2.9 are greater than that value. This means that when −2 ≤ f(x) ≤ 16 , we have two ranges -- from -3.4 to -1.3 and from 0.8 to 2.9 . Between -1.3 and 0.8, the function goes down then up, with all values less than f(x)=-2. Below -3.4 and above 2.9, all values are greater than f(x) = 16. One thing we can notice is that both ranges have a difference of approximately 2.1 between its high and low x values. The question asks for a value of a where a ≤ x ≤ a+3. As the difference between the high and low values are only 2.1, it would be impossible to have a range of greater than that.

Answer:

5+5t

Step-by-step explanation:

The answer you are looking for is t^3+3t^2+6t+4.

Solution:

(t+1)(t^2+2t+4)

t^3+2t^2+4t+t^2+2t+4

t^3+3t^2+6t+4

Answer:

(-1,-0.5)

Step-by-step explanation:

Find the solution to this problem by using the midpoint formula which is (x1+x2/2,y1+y2/2) plug in the values of y and x to get -11+9/2+0-1/2. simplify to get the solution of (-1,-0.5)

Answer: -1

Step-by-step explanation:

Look at the patter it has

Hey there!

Mode is basically the number(s) in a data plot you see MORE THAN once

• 18 appeared four times (this could be a possible answer)

• 17 appeared four times (this could be a possible answer)

• 19 appeared one time (this can’t be your answer)

• 20 appeared two times (this could be a possible answer)

Possible answers: 17,18, & 20

Since 17 & 18 appeared the MOST in the data plot those numbers could be your mode in your given data plot

Answer: 17 & 18

Good luck on your assignment and enjoy your day!

~Amphitrite1040:)

Answer:

(x,y) —> (–1 ,1)

I hope I helped you ^_^

Part (a)

Since we want segment AT to be an altitude, this means that point A is somewhere on segment RI such that angle TAI is 90 degrees. In other words, segments AT and RI are perpendicular. Check out the diagram below.

We'll need to find the slope of line RI, so we'll need the slope formula

R = (x1,y1) = (-2,-2)

I = (x2,y2) = (4,1)

m = slope of line RI

m = (y2-y1)/(x2-x1)

m = (1-(-2))/(4-(-2))

m = (1+2)/(4+2)

m = 3/6

m = 1/2

m = 0.5

The slope of line RI is 1/2 or 0.5

Now let's use point R(-2,-2) along with that slope we just found to find the equation of line RI.

Turn to point slope form

y - y1 = m(x - x1)

y - (-2) = 0.5(x -(-2))

y + 2 = 0.5(x + 2)

y + 2 = 0.5x + 1

y = 0.5x + 1 - 2

y = 0.5x - 1

This is the equation of line RI. We'll use it later.

----------

We found that the slope of line RI was 1/2.

The negative reciprocal involves us flipping the fraction and flipping the sign to get -2/1 or simply -2.

The perpendicular slope is -2. This is the slope of altitude AT.

We want line AT to go through T(-2,4), so we'll use this point along with the perpendicular slope we just found to calculate the equation of line AT.

We'll turn to the point slope form

y - y1 = m(x - x1)

y - 4 = -2(x - (-2))

y - 4 = -2(x + 2)

y - 4 = -2x - 4

y = -2x - 4 + 4

y = -2x

The equation of the line that goes through points A and T is y = -2x.

----------

To summarize so far, we have these two equations

Apply substitution to solve for (x,y) to find the intersection point. This will determine where point A is located.

y = 0.5x - 1

-2x = 0.5x - 1

-2x-0.5x = -1

-2.5x = -1

x = -1/(-2.5)

x = 0.4

Then we can determine y like so

y = -2x

y = -2(0.4)

y = -0.8

Therefore, point A is located at (0.4, -0.8). Both coordinate values are exact. In fraction form, we can say that the point is (2/5, -4/5), but I find decimals easier to work with in this instance.

===============================================================

Part (b)

To find the length of segment AT, we can find the distance from A to T. As you can probably guess, we'll use the distance formula.

A = (x1,y1) = (0.4, -0.8) ... found back in part (a)

T = (x2,y2) = (-2, 4) ... given

[tex]d = \sqrt{ (x_2-x_1)^2+(y_2-y_1)^2 }\\\\d = \sqrt{ (-2-0.4)^2+(4 - (-0.8))^2 }\\\\d = \sqrt{ (-2-0.4)^2+(4 + 0.8)^2 }\\\\d = \sqrt{ (-2.4)^2+(4.8)^2 }\\\\d = \sqrt{ 5.76+23.04 }\\\\d = \sqrt{ 28.8 }\\\\d \approx 5.36656\\\\d \approx 5.37\\\\[/tex]

The distance from point A to point T is approximately 5.37 units. This means that segment AT is roughly 5.37 units long.

consindering the equation ""yvariable m is the intercept ,,c constant

therefore from the equation by comparing...=mx+c where y

Answer:

See below.

Step-by-step explanation:

17.)

[tex]x+100+120+100=360\\x+320=360\\x=40[/tex]

18.)

[tex]x+150+77+48=360\\x+275=360\\x=85[/tex]

19.)

[tex]x+122+92+76=360\\x+290=360\\x=70[/tex]

20.)

[tex]x+115+85+60=360\\x+260=360\\x=100[/tex]

Answer:

Step-by-step explanation:

Hello!

x² + 5x-2

6² + 5*6 -2 =

36 +30 -2 =

66 -2=

64

Answer:

5

Step-by-step explanation:

It is 5 because you just have to count by using a jumping math tectechnique.

Answer:

x = 960

Step-by-step explanation:

Using the Altitude- on- Hypotenuse theorem

( leg of large triangle )² = ( part of hypotenuse below it) × ( whole hypotenuse), so

x² = 576 × (576 + 1024) = 576 × 1600 = 921600 ( take square root of both sides )

x = [tex]\sqrt{921600}[/tex] = 960

Answer:

96 flowers did not bloom and 12 did.

Explanation:

Total flower = 108

Number of flower that bloomed

= ⅑ of the total flowers

= ⅑ of 108

= ⅑ × 108

= 108/9

= 12

So, number of flowers that did not bloom

= Total flowers - Number of flowers that bloomed

= 108 - 12

= 96

So, 96 flowers did not bloom and 12 flowers did.

Answer:

Answer is option (B)......

Answer:

+ (+9) = -9  

Step-by-step explanation:

- (-9) = 9 A negative times a negative is a positive

- (+9) = -9   A negative times a positive is a negative

+ (-9) = -9  A positive times a negative is a negative

+ (+9) = -9 A positive time a positive is a positive

Answer:

5

Step-by-step explanation:

Use pythagorean theorem. A^2+B^2=C^2

13 is c because it is the hypotenuse and across from the right angle

a is unknown and b is 12

A^2+12^2=13^2

A^2 +144 = 169

A^2 = 169- 144

A^2= 25

now take the sq root of both side

A = 5

Answer:

17.7

Step-by-step explanation:

Answer:

Graph B

Explanation:

Answer:

1x>6-11

1x>-5

1x<-5

1 <1

x<-5/1

x<-5

Let

ATQ

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow 40x+50x=45000[/tex]

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow 90x=45000[/tex]

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow x=\dfrac{45000}{90}[/tex]

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow x=500[/tex]

Now

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow Rita=50x=50(500)=25000[/tex]

[tex]\\ \qquad\quad\sf{:}\twoheadrightarrow Mina=40x=40(500)=20000[/tex]

Answer:

실례합니다?

Step-by-step explanation:

질문이 뭔가요??? 이해가 안가요? 어느 언어?

Answer:

658ft

Step-by-step explanation:

you first have to calculate the angle next to that 28°angle,if you look at the two they form a 90° so to find that angle you have to subtract 90-28=62

the x is the opposite of angle 62 and the 350 si the adjacent so you can use the tan ratio to find the answer

tan62=opposite/adjacent

tan62=y/350

y=tan62×350

=658ft

I hope this helps

Answer:

0.02

Step-by-step explanation:

either picking a green then blue;

5/22 x 1/21= 5/462

or picking a blue then green;

1/22 x 5/21= 5/462

total is 10/462 which is approximately 0.02

since there was no specific order in the question i assumed you add them both.

Answer:

Square

Step-by-step explanation:

It got 4 sides like square and its form is looking like a square.

Answer:

B. XV and XY

Step-by-step explanation:

you can eliminate the top two options because those aren't rays. XV and XY are the only ones that end in X

Answer:

Step-by-step explanation:

Answer:

84

Step-by-step explanation:

To find the average of the data or the mean, add 75, 82, and 95 which is 252, then 252 divided by 3 = 84. Hopefully, this helps :)

Answer:

y=3/5x-1

Step-by-step explanation: