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3 years ago

Please help me, it would be really nice

Mathematics

1 answer:

77julia77 [94]3 years ago

6 0

4 Options bc its correct ome

You might be interested in

1. (You may get teacher help with this during tutoring)

Nezavi [6.7K]

Answer:

1A --- 25

1B --- (5 + 4) x 2 + 6 - 2 x 2 - 1 = 19

2A --- -206

2B --- ?

3A --- 5.8 × 10⁷

3B --- 2.5 × 10⁻³

4A --- 4.67 × 10¹³

4B --- 3.5 × 10⁻³

5A --- 9 × 10⁶

5B --- 1.68 × 10¹⁰

5C --- All ants combined weigh 112.46 times more than all humans combined

Step-by-step explanation:

(I am using PEMDAS for Order of Operations)

1A -----------------------------------------------

6 × 7 - 3² × 9 + 4³

Parenthesis

No parenthesis.

Exponents

6 × 7 - 3² × 9 + 4³

6 × 7 - 9 × 9 + 64

Multiplication

6 × 7 - 9 × 9 + 64

42 - 81 + 64

Division

No division.

Addition

42 - 81 + 64 (the 81 is negative)

42 + -17

1B --------------------------------------

5 + 4 x 2 + 6 - 2 x 2 - 1 = 14

(5 + 4) x 2 + 6 - 2 x 2 - 1 = 19

9 x 2 + 6 - 2 x 2 - 1

18 + 6 - 2 x 2 - 1

18 + 6 - 4 - 1

24 - 5

2A --------------------------------------------

3 × 7 - 3³ × 9 + 4²

Parenthesis

No parenthesis

Exponents

3 × 7 - 27 × 9 + 16

Multiplication

21 - 27 × 9 + 16

21 - 243 + 16

Addition

21 - 243 + 16

21 - 227

Subtraction

21 - 227

-206

2B ---------------------------------------------

5 + 3 × 2 + 6 - 2 × 3 - 7 = 4

(sorry cant figure this one out)

3A ------------------------------------------------

Move the decimal point in 58,000,000.0 over x times until you have 5.8000000. It was moved to the left 7 times, so the answer is 5.8 × 10⁷.

3B -----------------------------------------------

Move the decimal point in 0.0025 over x times until you have 2.5. It was moved to the right 3 times, so the answer is 2.5 × 10⁻³.

4A -----------------------------------------------

Move the decimal point in 46,700,000,000,000.0 x times until you have 4.67. It was moved to the left 13 times so the answer is 4.67 × 10¹³.

4B ----------------------------------------------

Move the decimal point in 0.0035 x times until you have 3.5. It was moved to the right 3 times, so the answer is 3.5 × 10⁻³.

5A -------------------------------------------------

(4.5 × 10³)(2 × 10³)

4.5 × 2 = 9

10³ × 10³ = 10⁶

9 × 10⁶

5B ------------------------------------------------------

(1.4 × 10⁵)(1.2 × 10⁵)

1.4 × 1.2 = 1.68

10⁵ * 10⁵ = 10¹⁰

1.68 × 10¹⁰

5C ---------------------------------------------------------

An adult human is 65 kilograms.

6.5 × 10¹ grams

An ant is (you didnt say how many so im going with) 5 grams.

5 × 10⁰ grams

6.84 billion humans

6,840,000,000.0 humans

6.84 × 10⁹ humans

10,000 trillion ants

1 × 10¹⁶ ants

Weight of humans:

(6.5 × 10¹)(6.84 × 10⁹)

44.46 × 10¹⁰

All humans weigh 4.446 × 10¹¹ kilograms

Weight of ants:

(5 × 10⁰)(1 × 10¹⁶)

All ants weigh 5 × 10¹⁶ grams

1000 grams per kilogram

1000 = 1 × 10³

5 × 10¹⁶ ÷ 1 × 10³

5 ÷ 1 = 5

16 - 3 = 13

All ants weigh 5 × 10¹³ kilograms

All humans weigh 4.446 × 10¹¹ kilograms

5 × 10¹³ ÷ 4.446 × 10¹¹ = 112.46

All ants combined weigh 112.46 times more than all humans combined

7 0

3 years ago

Find the equation of the line passing through point (4,2) and perpendicular to AB

Setler [38]

Answer:

a. -⅓

b. 3

c. y = 3x - 10

Step-by-step explanation:

a. Gradient of line AB:

A(1, 3), B(7, 1)

$Gradient = \frac{y_2 - y_1}{x_2 - x_1} = \frac{1 - 3}{7 - 1} = \frac{-2}{6} = -\frac{1}{3}$

Gradient (m) = -⅓

b. The of the line that is perpendicular to line AB would be the negative reciprocal of the gradient of line AB.

Thus, the negative reciprocal of -⅓ = 3

Gradient of the line perpendicular to line AB = 3

c. Equation of the line that passes through (4, 2) and is perpendicular to line AB:

We can write the equation using the point-slope form equation, y - b = m(x - a), where,

(a, b) represents a point on the line, and,

m = gradient/slope

We know that the gradient/slope (m) = 3

Also, a point, (a, b) = (4, 2).

Therefore, substitute a = 4, b = 2, and m = 3 into y - b = m(x - a)

Thus:

y - 2 = 3(x - 4)

y - 2 = 3x - 12

Add 2 to both sides

y = 3x - 12 + 2

y = 3x - 10

5 0

3 years ago

Gandalf the grey started in the forest of mirkwood at a point pp with coordinates (−2,1)(−2,1) and arrived in the iron hills at

AlladinOne [14]

Travel direction 3i + 2j, slope = 2/3.
We have slope and a point (-2,1) this gives us a line equation:
LINE BEFORE THE TURN, EQUATION: y = (2/3)x + 1

The point of intersection of the two lines:
1) through (-2,1) with slope 2/3 and;
2) through (-1,6) with slope 3/2.

8 0

3 years ago

A 75-gallon tank is filled with brine (water nearly saturated with salt; used as a preservative) holding 11 pounds of salt in so

Debora [2.8K]

Let $A(t)$ = amount of salt (in pounds) in the tank at time $t$ (in minutes). Then $A(0) = 11$ .

Salt flows in at a rate

$\left(0.6\dfrac{\rm lb}{\rm gal}\right) \left(3\dfrac{\rm gal}{\rm min}\right) = \dfrac95 \dfrac{\rm lb}{\rm min}$

and flows out at a rate

$\left(\dfrac{A(t)\,\rm lb}{75\,\rm gal + \left(3\frac{\rm gal}{\rm min} - 3.25\frac{\rm gal}{\rm min}\right)t}\right) \left(3.25\dfrac{\rm gal}{\rm min}\right) = \dfrac{13A(t)}{300-t} \dfrac{\rm lb}{\rm min}$

where 4 quarts = 1 gallon so 13 quarts = 3.25 gallon.

Then the net rate of salt flow is given by the differential equation

$\dfrac{dA}{dt} = \dfrac95 - \dfrac{13A}{300-t}$

which I'll solve with the integrating factor method.

$\dfrac{dA}{dt} + \dfrac{13}{300-t} A = \dfrac95$

$-\dfrac1{(300-t)^{13}} \dfrac{dA}{dt} - \dfrac{13}{(300-t)^{14}} A = -\dfrac9{5(300-t)^{13}}$

$\dfrac d{dt} \left(-\dfrac1{(300-t)^{13}} A\right) = -\dfrac9{5(300-t)^{13}}$

Integrate both sides. By the fundamental theorem of calculus,

$\displaystyle -\dfrac1{(300-t)^{13}} A = -\dfrac1{(300-t)^{13}} A\bigg|_{t=0} - \frac95 \int_0^t \frac{du}{(300-u)^{13}}$

$\displaystyle -\dfrac1{(300-t)^{13}} A = -\dfrac{11}{300^{13}} - \frac95 \times \dfrac1{12} \left(\frac1{(300-t)^{12}} - \frac1{300^{12}}\right)$

$\displaystyle -\dfrac1{(300-t)^{13}} A = \dfrac{34}{300^{13}} - \frac3{20}\frac1{(300-t)^{12}}$

$\displaystyle A = \frac3{20} (300-t) - \dfrac{34}{300^{13}}(300-t)^{13}$

$\displaystyle A = 45 \left(1 - \frac t{300}\right) - 34 \left(1 - \frac t{300}\right)^{13}$

After 1 hour = 60 minutes, the tank will contain

$A(60) = 45 \left(1 - \dfrac {60}{300}\right) - 34 \left(1 - \dfrac {60}{300}\right)^{13} = 45\left(\dfrac45\right) - 34 \left(\dfrac45\right)^{13} \approx 34.131$

pounds of salt.

7 0

2 years ago

X^3 plus 6x squared plus 3x minus−10x plus 5

Iteru [2.4K]

the answer is X^3+6x^2-7x+5

7 0

3 years ago