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Ray Of Light [21]
3 years ago
9

3a + 21 = 7 - 4a what's the answer

Mathematics
2 answers:
denis23 [38]3 years ago
8 0
After simplifying a= -2
scoundrel [369]3 years ago
5 0
3a + 21 = 7 - 4a

3a + 4a = 7 - 21

7 a = -14

a = - 14 / 7

a = - 2

hope this helps!
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Rigo and Ian went shopping for soccer cleats and practice uniforms. Rigo spent $451, before taxes, and purchased three uniforms
yan [13]

Answer:

The price of uniform U= $145

price of each pair of cleats C= $16

Step-by-step explanation:

Let:

The Price of Each Uniform = U

The Price of Each Pair of Cleats = C

Rigo spent $451, before taxes, and purchased three uniforms and one pair of cleats.

→ Equation A

Ian spent $757, before taxes, and purchased five uniforms and two pair of cleats.

→ Equation B

Let's calculate → 2(Equation A) - (Equation B)

2(3U+C)-(5U+2C)= 2(451) -757

6U+2C-5U-2C= 145

U=$ 145

3U+C= 451

3(145)+C= 451

C= 451-435

C= $16

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3 years ago
Explain how the sum and difference formula cos(A+/- B) = cosA cosB -/+ sinA sinB could be useful?
serg [7]
One way it's useful is in the application of phasors in physics. Phasors require you to add up vectors of two different angles, so the cosine angle addition formula can be used if you already know the cosine and sine of the original vector angles.
6 0
3 years ago
Read 2 more answers
calculate E, the amount of euros that has the same value as D U.S. dollars, using the equation E=17/20D=
Aleksandr [31]

<em>The given equation is:  E=17/20 D  , where  E=amount of Euros and D= amount of U.S dollar. </em>

<em> </em>

<em>Now for 1 U.S dollar, we need to plug D=1 into the above equation. So, we will get......... </em>

<em> E=17/20(1)</em>

<em>E=1/20=0.85</em>

<em>0.85 Euros have the same amount as 1 U.S dollar. </em>

<em> </em>

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8 0
3 years ago
The angle of inclination from the base of skyscraper A to the top of skyscraper B is approximately 12.8° If skyscraper B is 1479
melisa1 [442]

Answer:

6509.84 ft to the nearest hundredth.

Step-by-step explanation:

We have a right triangle in which the opposite side is 1479 ft and we need to find the adjacent side:

Tan 12.8 = opposite / adjacent side

tan 12.8 = 1479/ x

x = 1479/tan 12.8

= 6509.84 ft.

6 0
3 years ago
No links i will give you brainliest. please
CaHeK987 [17]

Answer:

n=radical of 28

Step-by-step explanation:

n^2=bc

n^2=28

n=radical of 28

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3 years ago
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