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S_A_V [24]
4 years ago
7

The sum of 3 number is 80. the third number is 3 times the first. the first number is 5 less the second. what are the numbers

Mathematics
1 answer:
Goshia [24]4 years ago
8 0
1st number = x-5
2nd number = x
3rd number = 3x-15
Total = 80
x-5+x+3x-15=80
5x-20=80
5x=100
x=20
The numbers are 20, 15, 45
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John’s parents recorded his height at various ages between 36 and 66 months.
timurjin [86]

Answer:

Step-by-step explanation:

a)General least square regression line is ,

Y=a+(b*x)

Where,a=intercept. b= slope

To get line just find values of a and b.

Use Excel to find values.

First enter values of variable "age" that is y in the column A that is A1to A5 and values of variable "height" in the column B, B1 to B5.

Then for value of a use functufuas ,

=INTERCEPT(A1:A5,B1:B5)

Then hit enter ,therefore a=20.4595

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Then hit enter.therefore b=0.3738

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Y=20.4595+(0.3738*x)

b) to predict height at age 21 years or 252 month just put value of x=252 in the above equation.

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3 years ago
What is an equation of the line that passes through the points (4,-1) and (8,5)?
fiasKO [112]

Answer:

y=3/2x-7

Step-by-step explanation:

the equation of the line for slope-intercept form is y=mx+b, where  m is the slope and b is the y intercept.

we are given two points: (4,-1) and (8,5)

the equation for slope is (y2-y1)/(x2-x1)

label the points:

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now substitute into the equation:

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the slope of the line is 3/2

here is our equation so far:

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we need to find b

since the equation will pass through the points, we can substitute either one into the equation to find b

let's use (4,-1) as an example

substitute into the equation

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hope this helps!

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emmasim [6.3K]

Answer:

Step-by-step explanation:

Prime factorize the given number. All factors should have pair. If all factors have pair, then it is a perfect square

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EG: 24: Factors of 12 are 2,2,3. Here 3 is without pair. so it is not a perfect square.

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Easy here
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