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3 years ago

PLEASE HELP‼

Mathematics

1 answer:

stellarik [79]3 years ago

4 0

D. 75 cm

Step-by-step explanation:

fill in the y with 20.5, so you get 20.5=0.3x-2. Add the 2 to the 20.5 so you get 22.5=0.3x. Divide both by 0.3 to get 75=x.

sorry if it's a bd explanation, hope this helps :)

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Suppose that the regression equation y = 16.99 + 0.32 x1 + 0.41 x2 + 5.31 x3 predicts an adult’s height (y) given the individual

umka21 [38]

Answer:

Step-by-step explanation:

It is given that the regression equation

$y = 16.99 + 0.32 x_1 + 0.41 x_2 + 5.31 x_3$

predicts an adult’s height (y) given the individual’s mother’s height (x1), his or her father’s height (x2), and whether the individual is male (x3 = 1) or female (x3 = 0).

The coefficient of x1 = 0.32 represents the increase in height of the child due to one inch increase in mother.

Similarly coefficient of x2 = 0.42 represents the increase in height of the child due to one inch increase in father.

and coefficient of x3 = 5.31 represents the increase in height of the child due to being a male than a female.

8 0

3 years ago

(50 points & Will give brainliest)

sweet-ann [11.9K]

Answer:

x = 3 , y = 13

Step-by-step explanation:

Note that both equations is equal to y. Set the two equations equal to each other

y = 7x - 8; y = 5x - 2

7x - 8 = y = 5x - 2

7x - 8 = 5x - 2

Isolate the x. Subtract 5x and add 8 to both sides

7x (-5x) - 8 (+8) = 5x (-5x) - 2 (+8)

7x - 5x = -2 + 8

Simplify.

(7x - 5x) = (-2 + 8)

2x = 6

Isolate the x. Divide 2 from both sides

(2x)/2 = (6)/2

x = 6/2

x = 3

---------------------------------------------------------------------------------------------------

Plug in 3 for x in one of the equations.

y = 7x - 8

y = 7(3) - 8

Simplify. Remember to follow PEMDAS.

y = 7(3) - 8

y = 21 - 8

y = 13

---------------------------------------------------------------------------------------------------

x = 3, y = 13 is your answer

4 0

3 years ago

Let C(n, k) = the number of k-membered subsets of an n-membered set. Find (a) C(6, k) for k = 0,1,2,...,6 (b) C(7, k) for k = 0,

vladimir1956 [14]

Answer:

(a) $C(6,0) = 1$ , $C(6,1) = 6$ , $C(6,2) = 15$ , $C(6,3) = 20$ , $C(6,4) = 15$ , $C(6,5) = 6$ , $C(6,6) = 1$ .

(b) $C(7,0) = 1$ , $C(7,1) = 7$ , $C(7,2) = 21$ , $C(7,3) = 35$ , $C(7,4) = 35$ , $C(7,5) = 21$ , $C(7,6) = 7$ , $C(7,7)=1$ .

Step-by-step explanation:

In this exercise we only need to recall the formula for C(n,k):

$C(n,k) = \frac{n!}{k!(n-k)!}$

where the symbol $n!$ is the factorial and means

$n! = 1\cdot 2\cdot 3\cdot 4\cdtos (n-1)\cdot n$ .

By convention 0!=1. The most important property of the factorial is $n!=(n-1)!\cdot n$ , for example 3!=1*2*3=6.

(a) The explanations to the solutions is just the calculations.

$C(6,0) = \frac{6!}{0!(6-0)!} = \frac{6!}{6!} = 1$

$C(6,1) = \frac{6!}{1!(6-1)!} = \frac{6!}{5!} = \frac{5!\cdot 6}{5!} = 6$

$C(6,2) = \frac{6!}{2!(6-2)!} = \frac{6!}{2\cdot 4!} = \frac{5!\cdot 6}{2\cdot 4!} = \frac{4!\cdot 5\cdot 6}{2\cdot 4!} = \frac{5\cdot 6}{2} = 15$

$C(6,3) = \frac{6!}{3!(6-3)!} = \frac{6!}{3!\cdot 3!} = \frac{5!\cdot 6}{6\cdot 6} = \frac{5!}{6} = \frac{120}{6} = 20$

$C(6,4) = \frac{6!}{4!(6-4)!} = \frac{6!}{4!\cdot 2!} = frac{5!\cdot 6}{2\cdot 4!} = \frac{4!\cdot 5\cdot 6}{2\cdot 4!} = \frac{5\cdot 6}{2} = 15$

$C(6,5) = \frac{6!}{5!(6-5)!} = \frac{6!}{5!} = \frac{5!\cdot 6}{5!} = 6$

$C(6,6) = \frac{6!}{6!(6-6)!} = \frac{6!}{6!} = 1$ .

(b) The explanations to the solutions is just the calculations.

$C(7,0) = \frac{7!}{0!(7-0)!} = \frac{7!}{7!} = 1$

$C(7,1) = \frac{7!}{1!(7-1)!} = \frac{7!}{6!} = \frac{6!\cdot 7}{6!} = 7$

$C(7,2) = \frac{7!}{2!(7-2)!} = \frac{7!}{2\cdot 5!} = \frac{6!\cdot 7}{2\cdot 5!} = \frac{5!\cdot 6\cdot 7}{2\cdot 5!} = \frac{6\cdot 7}{2} = 21$

$C(7,3) = \frac{7!}{3!(7-3)!} = \frac{7!}{3!\cdot 4!} = \frac{6!\cdot 7}{6\cdot 4!} = \frac{5!\cdot 6\cdot 7}{6\cdot 4!} = \frac{120\cdot 7}{24} = 35$

$C(7,4) = \frac{7!}{4!(7-4)!} = \frac{6!\cdot 7}{4!\cdot 3!} = frac{5!\cdot 6\cdot 7}{4!\cdot 6} = \frac{120\cdot 7}{24} = 35$

$C(7,5) = \frac{7!}{5!(7-2)!} = \frac{7!}{5!\cdot 2!} = 21$

$C(7,6) = \frac{7!}{6!(7-6)!} = \frac{7!}{6!} = \frac{6!\cdot 7}{6!} = 7$

$C(7,7) = \frac{7!}{7!(7-7)!} = \frac{7!}{7!} = 1$

For all the calculations just recall that 4! =24 and 5!=120.

6 0

3 years ago

6÷2(1+2)= ???????????

choli [55]

3(1+2)
3+6
9 ( the answer is nine)
first you divide six and two then use the distributive property to multiply three and one and three and two, then add three and six to get nine.

3 0

4 years ago

Three ballet dancers are positioned on stage. Elizabeth is straight behind Hannah and directly left of Manuel. If Hannah and Eli

ki77a [65]

Answer: Elizabeth and Manuel have a distance of 4 meters between them.

Step-by-step explanation: Please refer to the picture attached.

From the information given, Elizabeth is directly behind Hannah and directly left of Manuel. That means we have three points which are HEM, that is, we now have triangle HEM. The longest side (hypotenuse) which is the distance between Hannah and Manuel is given as 5 meters while the other side the distance between Hannah and Elizabeth is given as 3 meters.

We shall apply the pythagoras theorem in solving for the unknown side, EM.

The Pythagoras theorem states thus;

AC² = AB² + BC²

Where AC is the hypotenuse, and AB and BC are the other two sides.

Substituting for the known values, we now have;

5² = 3² + EM²

25 = 9 + EM²

Subtract 9 from both sides of the equation

16 = EM²

Add the square root sign to both sides of the equation

√16 = √EM²

4 = EM

Therefore the distance between Elizabeth and Manuel is 4 meters

8 0

3 years ago