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Mademuasel [1]
2 years ago
12

The sum of the first 15 terms of the sequence an=10n+21

Mathematics
1 answer:
enot [183]2 years ago
3 0
That is
the sum of all the terms from a1 to an when you are summing up n terms is n(a1+an)/2
so

find the 1st and 15th term
1st term is a1=10(1)=21=10+21=31
15th term is a15=10(15)+21=150+21=171

and n=15
15(31+171)/2=15(202)/2=3030/2=1515
the sum of the first 15 term is 1515
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Which set of coordinates, when paired with (-3, -2) and (-5, -2), result in a square?
taurus [48]
The answers are (-3, -4) and (-5, -4).
5 0
2 years ago
A craft vendor must sell at least $300 worth of merchandise to make a profit. Scarves sell for $10 each and hats sell for $20 ea
valina [46]
There is a missing graph in the problem given. However, we can simply solve the equation using the given data.

Items to be sold: scarves and hats. Minimum of 20 items sold in all.
Scarves sell for 10 each and hats sell for 20 each. Must sell at least 300 worth of merchandise to make profit. 

Let s represent scarves and h represent hats.

10s + 20h <u>></u> 300
s + h <u>></u> 20

We use inequality because the problem states "at least". 

s + h = 20
10s + 20h = 300

s = 20 - h
10(20-h) + 20h = 300
200 - 10h + 20h = 300
10h = 300 - 200
10h = 100
h = 100/10
h = 10

s = 20 - h
s = 20 - 10
s = 10

s + h <u>></u> 20
10 + 10 <u>></u> 20

10s + 20h <u>></u> 300
10(10) + 20(10) <u>></u> 300
100 + 200 <u>></u> 300

7 0
2 years ago
Read 2 more answers
A square has a side of 3x - 4 what is the area of the Square in terms of x?
Doss [256]

Answer:

9x2−24x+16

Hope this helps!

Step-by-step explanation:

The formula for a square is side times side since every side is of equal length. Because we are leaving the answer in terms of x you just multiply 3x-4 by 3x-4 and simplify and you get 9x2−24x+16

Please mark as brainliest :)

3 0
2 years ago
Which shows the correct substitution of the values a, b, and c from the equation 0 = – 3x2 – 2x + 6 into the quadratic formula?
lbvjy [14]

Answer:

x = StartFraction negative

(negative 2) plus or minus StartRoot (negative 2) squared minus 4 (negative 3)(6) EndRoot Over 2(negative 3) EndFraction

Step-by-step explanation:

0 = – 3x2 – 2x + 6

It can still be written as

– 3x2 – 2x + 6 =0

Quadratic formula=

-b+or-√b^2-4ac/2a

Where

a=-3

b=-2

c=6

x= -(-2)+ or-√(-2)^2-4(-3)(6)/2(-3)

x = StartFraction negative

(negative 2) plus or minus StartRoot (negative 2) squared minus 4 (negative 3)(6) EndRoot Over 2(negative 3) EndFraction

8 0
2 years ago
Round 21,253 to the nearest hundred.
Mazyrski [523]

Answer:

Hey there! The answer to your question is 21,300

Step-by-step explanation:

If we look at the 253 it is most close to 300 not 200 so the answer will be 21,300

Hope that helps!

By: xBrainly

6 0
2 years ago
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