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2 years ago

PLEASE HELP. Solve for x

Mathematics

1 answer:

sergejj [24]2 years ago

6 0

Answer:

x=8

Step-by-step explanation:

set up a proportion:

$\frac{20}{4}=\frac{4x-7}{5}$

simplify:

$5 =\frac{4x-7}{5}$

now solve this equation for x:

$5 = \frac{4x-7}{5} \\25 = 4x - 7\\32 = 4x\\x = 8$

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For what value of x is line a parallel to line b? Enter your answer in the box. X =____

Nezavi [6.7K]

Step-by-step explanation:

115 = 5x + 15

115 - 15 = 5x

100 = 5x

20 = x

7 0

2 years ago

A storekeeper has two kinds of flour, one selling for 65 cents per pound, and the other selling for 95 cents per pound. How many

Murrr4er [49]

Answer:

The amount of 65 cents per pound flour to use is 40 pounds and the amount of 95 cents per pound flour to use is 60 pounds

Step-by-step explanation:

Let

x ----> amount of 65 cents per pound flour to use

y----> amount of 95 cents per pound flour to use

we know that

$x+y=100$ ----> $y=100-x$ ----> equation A

$0.65x+0.95y=0.83(100)$ ----> equation B

substitute equation A in equation B

$0.65x+0.95(100-x)=0.83(100)$

Solve for x

$0.65x+95-0.95x=83$

$0.95-0.65x=95-83$

$0.30x=12$

$x=40\ lb$

Find the value of y

$y=100-40=60\ lb$

therefore

The amount of 65 cents per pound flour to use is 40 pounds and the amount of 95 cents per pound flour to use is 60 pounds

4 0

2 years ago

Read 2 more answers

SQUARE ROOT OF 8<br><br>THANKS -,-

sergey [27]

Answer:

it's 2

Step-by-step explanation:

square root of 8 is 2

5 0

2 years ago

Read 2 more answers

The Apple harvest produced 2,350kg of Apple's. A farmer packs 36 apples in the box. One apple weighs approximately 250 grams how

jenyasd209 [6]

Answer:

Step-by-step explanation:

The total number of apples produced at the apple harvest is 2,350kg.

1 kg = 1000 grams. Therefore,

2350 kg = 2350 × 1000 = 2350000kg

A farmer packs 36 apples in the box. If one apple weighs approximately 250 grams, the total weight of 36 apples would be

36 × 250 = 9000 grams

Therefore, the number of boxes that are needed to pack the apples would be

2350000/9000 = 261.11

It means that 262 boxes would be needed.

5 0

2 years ago

Determine formula of the nth term 2, 6, 12 20 30,42

nalin [4]

Check the forward differences of the sequence.

If $\{a_n\} = \{2,6,12,20,30,42,\ldots\}$ , then let $\{b_n\}$ be the sequence of first-order differences of $\{a_n\}$ . That is, for n ≥ 1,

$b_n = a_{n+1} - a_n$

so that $\{b_n\} = \{4, 6, 8, 10, 12, \ldots\}$ .

Let $\{c_n\}$ be the sequence of differences of $\{b_n\}$ ,

$c_n = b_{n+1} - b_n$

and we see that this is a constant sequence, $\{c_n\} = \{2, 2, 2, 2, \ldots\}$ . In other words, $\{b_n\}$ is an arithmetic sequence with common difference between terms of 2. That is,

$2 = b_{n+1} - b_n \implies b_{n+1} = b_n + 2$

and we can solve for $b_n$ in terms of $b_1=4$ :

$b_{n+1} = b_n + 2$

$b_{n+1} = (b_{n-1}+2) + 2 = b_{n-1} + 2\times2$

$b_{n+1} = (b_{n-2}+2) + 2\times2 = b_{n-2} + 3\times2$

and so on down to

$b_{n+1} = b_1 + 2n \implies b_{n+1} = 2n + 4 \implies b_n = 2(n-1)+4 = 2(n + 1)$

We solve for $a_n$ in the same way.

$2(n+1) = a_{n+1} - a_n \implies a_{n+1} = a_n + 2(n + 1)$

Then

$a_{n+1} = (a_{n-1} + 2n) + 2(n+1) \\ ~~~~~~~= a_{n-1} + 2 ((n+1) + n)$

$a_{n+1} = (a_{n-2} + 2(n-1)) + 2((n+1)+n) \\ ~~~~~~~ = a_{n-2} + 2 ((n+1) + n + (n-1))$

$a_{n+1} = (a_{n-3} + 2(n-2)) + 2((n+1)+n+(n-1)) \\ ~~~~~~~= a_{n-3} + 2 ((n+1) + n + (n-1) + (n-2))$

and so on down to

$a_{n+1} = a_1 + 2 \displaystyle \sum_{k=2}^{n+1} k = 2 + 2 \times \frac{n(n+3)}2$

$\implies a_{n+1} = n^2 + 3n + 2 \implies \boxed{a_n = n^2 + n}$

6 0

1 year ago