Simplify 4(x-3) + 2x e5

The difference of the square of a number and 40 is equal to 3 times that number. Find the positive solution.

Wewaii [24]

Answer: The answer is 8.

Step-by-step explanation: The first step is to convert the expression into figures. We shall call the unknown number Y. So if we are told “the square of a number,” that means Y squared, or better still, Y^2. Further we are told “the difference between the square of a number and 40” and that can be written as;

Y^2 - 40.

Next we are told that this expression is equal to 3 times that number (that is 3Y). That can now be written out as follows,

Y^2 - 40 = 3Y

If we move all expressions to one side of the equation, what we would have is,

Y^2 - 3Y -40 = 0

(Remember that when a positive value crosses to the other side of an equation it becomes negative and vice versa)

We now have a quadratic equation

Y^2 -3Y - 40 = 0

By factorizing we now have

(Y -8) (Y + 5) = 0

Therefore Y - 8 = 0 or

Y + 5 = 0

Hence, Y = 8 or Y = -5

Since we are asked to calculate the positive solution, Y = 8

5 0

3 years ago

Two different radioactive isotopes decay to 10% of their respective original amounts. Isotope A does this in 33 days, while isot

Molodets [167]

It should be c cause I just took the test

4 0

3 years ago

Read 2 more answers

Write the equation of a parabola with focus at (1,-4) and a directrix at X=2

konstantin123 [22]

Answer:

The equation of a parabola is

$x = \frac{1}{4(f - h)} (y - k) ^{2} + h$

Step-by-step explanation:

(h,k) is the vertex and (f,k) is the focus.

Thus, f = 1, k = −4.

The distance from the focus to the vertex is equal to the distance from the vertex to the directrix: f - h = h - 2.

Solving the system, we get h = 3/2, k = -4, f = 1.

The standard form is:

$x = - \frac{y ^{2} }{2} - 4y - \frac{13}{2}$

The general form is:

$2x + {y}^{2} + 8y + 13 = 0$

The vertex form is:

$x = - \frac{(y + 4) ^{2} }{2} + \frac{3}{2}$

The axis of symmetry is the line perpendicular to the directrix that passes through the vertex and the focus: y = -4.

The focal length is the distance between the focus and the vertex: 1/2.

The focal parameter is the distance between the focus and the directrix: 1.

The latus rectum is parallel to the directrix and passes through the focus: x = 1.

The length of the latus rectum is four times the distance between the vertex and the focus: 2.

The eccentricity of a parabola is always 1.

The x-intercepts can be found by setting y = 0 in the equation and solving for x.

x-intercept:

$( - \frac{13}{2} \: ,0)$

The y-intercepts can be found by setting x = 0 in the equation and solving for y.

y-intercepts:

$(0, - 4 - \sqrt{3)}$

$(0, - 4 + \sqrt{3)}$

3 0

2 years ago

suppose that the population of deer in a state is 1,500 and is growing 2% each year. Predict the population after 4 years

Neko [114]

1500(1+0.02)^4=1,623.64824

6 0

3 years ago

Find the midpoint of the line segment with the endpoints A and B.<br> A(10,6); B(8,4)

MatroZZZ [7]

Answer:

(9,5)

Step-by-step explanation:

10+8/2=18/2=9

6+4/2=10/2=5

4 0

2 years ago