All categories

2 years ago

Please answer quickly, I will mark you brainiest

Mathematics

2 answers:

mariarad [96]2 years ago

6 0

Answer: x=3 or x=-3

Step-by-step explanation: Step 1: Add 3 to both sides, Step 2: Divide both sides by 1/3, Step 3: Take square root.

yan [13]2 years ago

5 0

Answer:

The answer is x = -3, 3

Step-by-step explanation:

You might be interested in

The rate of change of the number of mountain lions N(t) in a population is directly proportional to 725 - N(t), where t is the t

wolverine [178]

Answer:

a) The implied differential equation is $\frac{dN}{725 - N} = kdt$

b) The general equation is $N = 725 - C e^{-kt}$

c) The particular equation is $N = 725 - 325 e^{-0.49t}$

d) The population when t = 5, N(5) = 697 = 700( to the nearest 50)

Step-by-step explanation:

The rate of change of N(t) can be written as dN/dt

According to the question, $\frac{dN}{dt} \alpha (725 - N(t))$

$\frac{dN}{dt} = k (725 - N)\\\frac{dN}{725 - N} = kdt$

Integrating both sides of the equation

$\int {\frac{1 }{725 - N}} \, dN = \int {k} \, dt\\- ln (725 - N) = kt + C\\ ln (725 - N) = -(kt + C)\\725 - N = e^{-(kt + C)} \\725 - N = e^{-kt} * e^{-C} \\725 - N = C e^{-kt}\\N = 725 - C e^{-kt}$

When t = 0, N = 400

$400 = 725 - C e^{-k*0}\\400 = 725 - C\\C = 725 - 400\\C = 325$

When t = 3, N = 650

$650 = 725 - (325 * e^{-3k})\\325 * e^{-3k} = 75\\e^{-3k} = 75/325\\e^{-3k} = 0.23\\-3k = ln 0.23\\-3k = -1.47\\k = 1.47/3\\k = 0.49$

The equation for the population becomes:

$N = 725 - 325 e^{-0.49t}$

At t = 5, the population becomes:

$N = 725 - 325 e^{-0.49*5}\\N = 725 - 325 e^{-2.45}\\N = 696.95\\N(5) = 697$

N(5) = 700 ( to the nearest 50)

6 0

2 years ago

The quadratic formula gives which roots for the equation 2x^2 + x - 6 = 0?

Jet001 [13]

Answer:

The roots are $x = (\frac{3}{2}, -2)$ , which is given by option C.

Step-by-step explanation:

Solving a quadratic equation:

Given a second order polynomial expressed by the following equation:

$ax^{2} + bx + c, a\neq0$ .

This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

$x_{1} = \frac{-b + \sqrt{\Delta}}{2*a}$

$x_{2} = \frac{-b - \sqrt{\Delta}}{2*a}$

$\Delta = b^{2} - 4ac$

In this question, we have that:

$2x^2 + x - 6 = 0$

Which is a quadratic equation with $a = 2, b = 1, c = -6$ . So

$\Delta = 1^{2} - 4*2(-6) = 1 + 48 = 49$

$x_{1} = \frac{-1 + \sqrt{49}}{2*2} = \frac{6}{4} = \frac{3}{2}$

$x_{2} = \frac{-1 - \sqrt{49}}{2*2} = \frac{-8}{4} = -2$

So the roots are $x = (\frac{3}{2}, -2)$ , which is given by option C.

3 0

2 years ago

Can some please help me!

serious [3.7K]

Answer:

f-53=389

Step-by-step explanation:

4 0

2 years ago

Read 2 more answers

At a pet store, there are 30 aquariums.

irakobra [83]

Answer:

f = (20 × 15) + (10 × 6)

Explanation:

You are just find how many fish are salt water and how many freshwater and adding them together. The total number of aquariums is irrelevant in this case.

8 0

2 years ago

Sarah bought a bike that cost $260. She had a coupon that was worth $55 off the cost of any bike. Use the expression 260 + (−55)

aleksklad [387]

Answer:

$205

Step-by-step explanation:

The cost of bike Sarah bought = $260

Discount coupon = $55

The cost Sarah paid for the bike =$260 - $55

Use the expression 260 + (- 55) to find how much Sarah paid for her bike:

$260+(-55)\\ \\=200+60+(-55)\\ \\=200+5+55+(-55)\ [\text{Note} 55+(-55)=0]\\ \\=200+5\\ \\=205$

So, Sarah paid $205 for the bike.

4 0

3 years ago