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2 years ago

A series contains 18 numbers and has a sum of 4,185. The last number of the series is 275. What is the first number?

1 answer:

3 0

The sum of arithmetic series is given by:
Sn=n/2(a1+an)
where:
n=number of terms
a1=first term
an=nth term
but
n=18, an=275, Sn=4185
plugging the values in the formula we get:
4185=18/2(a1+275)
simplifying this we get:
4185=9(a1+275)
dividing through by 9 we get:
465=a1+275
thus
a1=465-275
a1=190

Answer: first number is 190

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Solve 7x- c= k for x. <br>A. X = 7(k+C) <br>B. x = 7(K-C) <br>C. X = k+c/7 <br>D. X= k-c/7

antoniya [11.8K]

Answer:

Step-by-step explanation:

you add c to both side which will then make it 7x=k+c then you would divide 7 from both sides leaving you with x=k+c/7. Except 7 will be under the k and c.

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2 years ago

What algebraic expression represents GK, if GK =37, what are GH and JK. GJ=4x+2 and HK=6x-1

torisob [31]

Answer:

The answer is "GK=37, GH=14, and JK=19 ".

Step-by-step explanation:

In the question, an attachment file is missing.so, please find its attached file.

Given values:

GJ=4x+2

HK=6x-1

GK =37

Find:

HJ=?

GK = GJ+JK

= GJ+(HK-HJ)

= 4x+2+((6x-1)-x)

= 4x+2+6x-1-x

9x+1...(a)

Solve equation (a) and put the value of x in the equation:

=9(4)+1

=36+1

=37

find GH and JK=?

Given:

GK=37

Formula:

GH = GJ-HJ

= 4x+2- x

= 3x+2....(b)

Solve equation (a):

GK= 9x+1

37=9x+1

36=9x

x=4....(c)

put the value of equation (b) in equation (c)

GH = 3x+2

= 3(4)+2

= 12+2

= 14

Formula:

JK= HK-HJ

= 6x-1- x

= 5x-1

put the value of x in the above equation:

= 5(4)-1

= 20-1

=19

8 0

2 years ago

Which are the solutions of x2 = –11x + 4? StartFraction negative 11 minus StartRoot 137 EndRoot Over 2 EndFraction comma StartFr

Marysya12 [62]

Answer:

$x_1=-\frac{11}{2}-\frac{\sqrt{137} }{2}\\\\x_2=-\frac{11}{2}+\frac{\sqrt{137} }{2}$

Step-by-step explanation:

Given the following quadratic equation:

$x^2 = -11x + 4$

The steps to solve it are:

1. Move the terms to one side of the equation:

$x^2+11x- 4=0$

2. Apply the Quadratic formula $x=\frac{-b\±\sqrt{b^2-4ac} }{2a}$ .

In this case we can identify that:

$a=1\\b=11\\c=-4$

Then, substituting these values into the Quadratic formula we get the following solutions:

$x=\frac{-11\±\sqrt{11^2-4(1)(-4)} }{2(1)}$

$x_1=-\frac{11}{2}-\frac{\sqrt{137} }{2}\\\\x_2=-\frac{11}{2}+\frac{\sqrt{137} }{2}$

3 0

2 years ago

Read 2 more answers

En las competencias de atletismo hay 120 participantes; 30 en la prueba de 100 m, 50 en la de 200 m y 40 en la carrera de relevo

IceJOKER [234]

Answer:

120 by the questiom we have tl do plus or not

7 0

2 years ago

Will works 7 hours a day, 6 days a week.

exis [7]

A day
= £9.20x7
= £64.40

6 days
£64.40x6= £386.40

The wages he has after he shared it with his mom
£386.40/7x5
= 55.20x5
= £276

£1932/£276= 7

It will take him 7 weeks to afford a car worth £1932.

6 0

2 years ago