-4/5 - (-2/5) + 4/7 evaluate the expression help plz

Answer:

(a) 30 feet

(b) 30 feet.

Step-by-step explanation:

Given that the opening of a tunnel that travels through a mountainside can be modeled by

[tex]y=\frac{-2}{15} (x-15)(x+15)[/tex], where x and y are measured in feet.

[tex]\Rightarrow y=\frac{-2}{15}(x^2-15^2}[/tex]

[tex]\Rightarrow y=\frac{-2}{15}{x^2-225}\cdots(i)[/tex]

(a) At the ground level, [tex]y=0[/tex]

So, the width of the tunnel at ground level is distance between the extreme point of the tunnel on the grount.

For, [tex]y=0[/tex], the extreme points of the tunnel.

[tex]0=\frac{-2}{15} (x-15)(x+15)[/tex]

[tex]\Rightarrow (x-15)(x+15) =0[/tex]

[tex]\Rightarrow x= 15, -15[/tex]

So, the extreme points of the tunnel are, [tex]x_1=15[/tex] and [tex]x_2=-15[/tex].

Hence, the width of the tunnel at the ground level

[tex]= | x_1 - x_2 |[/tex]

[tex]=|15-(-15)|[/tex]

[tex]=30[/tex] feet.

(b) The maximum height of the tunnel can be determiment by determining the maxima of the given function.

First determining the value of x for which the slope of the graph is zero.

[tex]\frac{dy}{dx}=0[/tex]

From equation (i),

-2x=0

[tex]\Rightarrow x=0[/tex]

And  [tex]\frac{d^2y}{dx^2}= -2[/tex]

which is always negative, so at x=0 the value of y is maximum.

Again, put x=0 in equation (i), we have

[tex]y=\frac{-2}{15}{0^2-225}[/tex]

[tex]\Rightarrow y=30[/tex] feet.

Hence, the tunnel is 30 feet tall.

Answer:

134

Step-by-step explanation:

Your answer is simply 134

hey mate☺️☺️ here's your answer......

4x'4 + 1

Answer:

(2x - 9)(2x + 9)

Step-by-step explanation:

4x^2 - 81 = (2x - 9)(2x + 9)

Answer:

(2x+9)(2x-9)

Step-by-step explanation:

kind of simple actually

4x^2-81=(2x+9)(2x-9)

Answer:

false

Step-by-step explanation:

all rectangles are squares not all squares are rectangles

Answer:

$5.58

Step-by-step explanation:

Because divide 12 by 67:

67 ÷ 12 = 5.58

5.58 is the answer

Hope this helped! Pls Brainliest!

Answer:

$5.58

Step-by-step explanation:

$67.00÷12=$5.58

Hope this helps!

Answer:

2447.40

Step-by-step explanation:

48,948 * .05 = 2447.40

Answer:

2447.40 that the answer

Question:

Find the probability of getting a doublet in a throw of a pair of dice.

Answer:

The probability is 1 out of 6.

Explanation:

There are a total of 6 possibilities that you get a doublet, which is {1, 1}, {2, 2}, {3, 3}, {4, 4}, {5, 5}, and {6, 6}.

The total possibilities of throwing a dice are 6 possibilities for the first dice, and 6 possibilities for the second dice. Which results in a total of 6 × 6 = 36 possibilities available.

Probability = Possibilities of getting doublet ÷ Total possibilities = 6 ÷ 36 = 1 ÷ 6.

Hopefully this answer will help you.

Step-by-step explanation:

A + B = 0

A = -B

(-B)B) = -36

-B^2 = -36

B^2 = 36

B = 6, -6

So, A = -6, 6

A - B = -12

or

A - B = 12

Answer:

A - B = ± 12

Step-by-step explanation:

Given

A + B = 0  → (1)

AB = - 36 → (2)

Subtract B from both sides of (1)

A = - B ← substitute into (2)

- B(B) = - 36 ( multiply both sides by 0 1 )

B² = 36 ( take square root of both sides )

B = ± 6

Substitute into (1)

If B = 6 then A =- 6 and A-B = - 6 - 6 = - 12

If B = - 6 then A = 6 and A - B = 6 - (- 6) = 6 + 6 = 12

Answer:

[tex]y = - 2x + 7[/tex]

you can see from graph that line is going through (0,7) and (5,-3) and that is enough to fine the equation of a line using formula

[tex]y-y_1= \frac{y_2-y_1}{x_2-x_1} \times (x-x_1)[/tex]

Answer: B  

(Use the distributive property on each side of the equation.)

Step-by-step explanation:

Answer: 7:35 a. M

Step-by-step explanation:

Given that:

Snooze on alarm = 5 minutes

Snooze on cellphone = 7 minutes

If both activates at 7:00 a. M

Time at which both will activate again ;

Obtain the Lowest Common Multiple of 5 and 7

_5 __|5 ___|7

_7__ |1 ___|7

____ |1 ___| 1

Lowest common multiple = (5 * 7) = 35

Hence, both alarms will sound together again after 35 minutes = 7:00a.m + 35 minutes = 7:35 A. M

Answer:

23,999

Step-by-step explanation:

Un refrigerador de $8,500.50

Un televisor de $3,500.50

Una computadora de $6,900.00

Una lavadora de $4,999.00

8,500.50 + 3,500.50 + 6,999.00 + 4,999.00 = 23,999.00

Answer:c

Step-by-step explanation:

Answer:

a) [tex]\sqrt{90}[/tex]

Step-by-step explanation:

The square root of 90 is approximately 9.487.

Answer:

x=4

Step-by-step explanation:

-9=-x-5

-9+5=-x

-4=-x

x=4

Answer:

2^2 x 5 x 9.

Step-by-step explanation:

This will give you the answer because when multiplying all of this you will get 180. Answer B.

Answer:

Distributive property

Answer:

$24,970

Step-by-step explanation:

22,000+(99,000•0.03)=22,000+2,970=24,970

Answer:

Step-by-step explanation:

a: 2

b: 4

c: 3

d: 4

e: 6

Answer:

Hello!!! Princess Sakura here ^^

Step-by-step explanation:

So all you have to do is use long division because a calculator won't help you with this if you are looking for a remainder so basically you just divide then you will get...

[tex]\frac{859}{3}=?\\?=286 R: 1[/tex]

So the answer is 286 and a remainder of 1.

The result of the division problem ; with the quotient and remainder respectively are 286 and 1

__ 286 ______quotient

______

3 | 859

__6

-

__259

__24

-___19

-___18

____1 ________ remainder

Therefore, the quotient and remainder of the divison expression are 286 and 1

Learn more : https://brainly.com/question/15165519

Answer:

14

Step-by-step explanation:

5+(3*3)

5+9

14

Answer:

1) 4x^(2)+11x+6 Factored--> (4x+3) (x+2)

2) 4x^(2)+10x+6 Factored--> (2x+3)(2x+2)

3) 4x^(2)+14x+6 Factored--> (x+3)(4x+2)

Step-by-step explanation:

Factor: 4x^(2)+11x+6 (step by step)

1) Split the second term (11x) into two terms

      4x^2 + 8x + 3x + 6

2)Factor out common terms in the first two terms, then in the last two terms.

      4x(x + 2) + 3(x + 2)

3) Factor out the common term x + 2

      (x + 2) (4x + 3)

Repeat the above steps for similar questions!

Answer:

$800 per 40 hours

Step-by-step explanation:

In photo