Fill in the missing numbers in these equation <br> (-2) . (-4.5)= ? <br> ?=

Q(a+1) - 2q(a) if q(x) = x²+3x+4

siniylev [52]

$q(x) = {x}^{2} + 3x + 4$

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Step(1)

To find q(a) we just need to put a instead of x in q(x) function.

Let's do it...

$q(a) = {a}^{2} + 3a + 4$

Multiply sides by -2 :

$- 2q(a) = - 2( {a}^{2} + 3a + 4)$

$- 2q(a) = - 2 {a}^{2} - 6a - 8$

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Step (2)

To find q(a+1) we just need to put a+1 instead of x in q(x) function.

Let's do it...

$q(a + 1) = ({a + 1})^{2} + 3(a + 1) + 4 \\$

$q(a + 1) = {a}^{2} + 2a + 1 + 3a + 3 + 4 \\$

$q(a + 1) = {a}^{2} + 5a + 8$

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Step (3)

$q(a + 1) - 2q(a) =$

${a}^{2} + 5a + 8 - 2 {a}^{2} - 6a - 8 = \\$

$- {a}^{2} - a = - a(a + 1)$

And we're done.

Thanks for watching buddy good luck.

♥️♥️♥️♥️♥️

8 0

4 years ago

Find the number of the different ways, for 3 students to sit on 7 seats in one row.

qwelly [4]

Answer:

210

Step-by-step explanation:

Here comes the problem from Combination.

We are being asked to find the number of ways out in which 3 students may sit on 7 seats in a row. Please see that in this case the even can not be repeated.

Let us start with the student one. For him all the 7 seats are available to sit. Hence number of ways for him to sit = 7

Let us see the student second. For him there are only 6 seats available to sit as one seat has already been occupied. Hence number of ways for him to sit = 6

Let us see the student third. For him there are only 5 seats available to sit as two seat has already been occupied. Hence number of ways for him to sit = 5

Hence the total number of ways for three students to be seated will be

7 x 6 x 5

=210

3 0

3 years ago

Read 2 more answers

The diameter of the average cell in the human body is 1 x 10-5 meters. The diameter of a grain of sand is about 2 x 10-4 meters.

MariettaO [177]

PART A:

Scientific notation is given by A×10ⁿ where A is any number in a unit and 'n' is an integer.

0.000025 = 2.5×10⁻⁵

PART B:

Diameter of grain of sand ÷ Diameter of human body average cell
(2×10⁻⁴) ÷ (1×10⁻⁵)
(2÷1) × (10⁻⁴÷10⁻⁵)
2 × (10⁻⁴ ⁻ ⁻⁵) = 2 × 10⁽⁻⁴⁺⁵⁾ = 2 × 10¹ = 20 times bigger

PART C:

The diameter of human body's average cell in nanometer
1 × 10⁻⁵ metre = 1 × 10⁻⁵ × 10⁹ = 1 × 10⁽⁻⁵⁺⁹⁾ = 1 × 10⁴ nanometer

PART D:

Smallest bacteria = 300 nanometer
300 nm = 300 ÷ 10⁹ = (3 × 10²) ÷ 10⁹ = 3 × (10²⁻⁹) = 3 × 10⁻⁷ meter

PART E:

Laws of exponents that are applied in scientific notation is

xᵇ × xᵃ = x⁽ᵇ⁺ᵃ⁾
xᵇ ÷ xᵃ = x⁽ᵇ⁻ᵃ⁾

7 0

3 years ago

Point B has coordinates (1,2). The x-coordinate of point A is -8. The distance between point A and point B is 15 units. What

Xelga [282]

Answer:

The possible coordinates of point A are $A_{1} (x,y) = (-8, 14)$ and $A_{2} (x,y) = (-8, -10)$ , respectively.