All categories

2 years ago

40=3x+x^2 How do I find the answer to this

Mathematics

1 answer:

tamaranim1 [39]2 years ago

8 0

Answer:

x = -8, x = 5

Step-by-step explanation:

This can be solved using Factorization method:

$40 = 3x + {x}^{2} \\ \\ \implies \: {x}^{2} + 3x - 40 = 0 \\ \\ \implies \: {x}^{2} + 8x - 5x- 40 = 0 \\ \\ \implies \: x({x} + 8) - 5(x + 8) = 0 \\ \\ \implies \: ({x} + 8) (x - 5) = 0 \\ \\ \implies \: ({x} + 8) = 0 \: \: or \: \: (x - 5) = 0 \\ \\ \implies \: x = - 8 \: \: or \: \: x = 5 \\ \\ x = - 8, \: \: 5$

You might be interested in

Write the polynomial in factored form. <br><br> p(x)=(x+5)(x-___)(x+___)

Rom4ik [11]

Answer:

Step-by-step explanation:

Given : $p(x)=x^{3} +6x^{2} -7x-60$

Solution :

Part A:

First find the potential roots of p(x) using rational root theorem;

So, $\text{Possible roots} =\pm\frac{\text{factors of constant term}}{\text{factors of leading coefficient}}$

Since constant term = -60

Leading coefficient = 1

$\text{Possible roots} =\pm\frac{\text{factors of 60}}{\text{factors of 1}}$

$\text{Possible roots} =\pm\frac{1,2,3,4,5,6,10,12,15,20,60}{1}$

Thus the possible roots are $\pm1, \pm2, \pm 3, \pm4, \pm5,\pm6, \pm10, \pm12, \pm15, \pm20, \pm60$

Thus from the given options the correct answers are -10,-5,3,15

Now For Part B we will use synthetic division

Out of the possible roots we will use the root which gives remainder 0 in synthetic division :

Since we can see in the figure With -5 we are getting 0 remainder.

Refer the attached figure

We have completed the table and have obtained the following resulting coefficients: 1 , 1,−12,0. All the coefficients except the last one are the coefficients of the quotient, the last coefficient is the remainder.

Thus the quotient is $x^{2} +x-12$

And remainder is 0 .

So to get the other two factors of the given polynomial we will solve the quotient by middle term splitting

$x^{2} +x-12=0$

$x^{2} +4x-3x-12=0$

$x(x+4)-3(x+4)=0$

$(x-3)(x+4)=0$

Thus x-3 and x+4 are the other two factors

So , p(x)=(x+5)(x-3)(x+4)

3 0

3 years ago

Read 2 more answers

Suppose a population of honey bees in Ephraim, UT has an initial population of 2300 and 12 years later the population reaches 13

Rama09 [41]

Answer:

common ratio: 1.155

rate of growth: 15.5 %

Step-by-step explanation:

The model for exponential growth of population P looks like: $P(t)=P_i(1+r)^t$

where $P(t)$ is the population at time "t",

$P_i$ is the initial (starting) population

$(1+r)$ is the common ratio,

and $r$ is the rate of growth

Therefore, in our case we can replace specific values in this expression (including population after 12 years, and initial population), and solve for the unknown common ratio and its related rate of growth:

$P(t)=P_i(1+r)^t\\13000=2300*(1+r)^{12}\\\frac{13000}{2300} = (1+r)^12\\\frac{130}{23} = (1+r)^{12}\\1+r=\sqrt[12]{\frac{130}{23} } =1.155273\\$

This (1+r) is the common ratio, that we are asked to round to the nearest thousandth, so we use: 1.155

We are also asked to find the rate of increase (r), and to express it in percent form. Therefore we use the last equation shown above to solve for "r" and express tin percent form:

$1+r=1.155273\\r=1.155273-1=0.155273$