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2 years ago

How do you solve -3x+y=7 5x+2y=3 by substitution method??

Mathematics

2 answers:

JulsSmile [24]2 years ago

8 0

Yes you would have to solve this problem by substitution method

lakkis [162]2 years ago

8 0

Answer:

(-1,4)

Step-by-step explanation:

-3x + y = 7......y = 3x + 7

so sub in 3x + 7 in for y back into the other equation

5x + 2y = 3

5x + 2(3x + 7) = 3 ...distribute thru the parenthesis

5x + 6x + 14 = 3....subtract 14 from both sides

5x + 6x = 3 - 14...combine like terms

11x = - 11...divide both sides by 11

x = -11/11

x = -1

now that we know x = -1, we can sub that back into either of the original equations to find y

y = 3x + 7

y = 3(-1) + 7

y = -3 + 7

y = 4

so we have (-1,4) as a solution....but lets check it first

-3x + y = 7

-3(-1) + 4 = 7

3 + 4 = 7

7 = 7 (correct)...it checks out

so ur solution is : x = -1 and y = 4 or (-1,4)

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3−2x=2x+3(6−3x)−7(1−2y)=25+6y

Zielflug [23.3K]

Answer:

Step-by-step explanation:

First you need to use the distributive property:

3-2x+2x+3(6-3x)-7(1-2y)=25+6y

3-2x=2x+18-9x-7+14y=25+6y

3-2x=-7x+11+14y=25+6y

Then Split up the equations.

3-2x=-7x+11

Subtract 3 from both sides

-2x=-7x+8

Then add -7x to both sides

5x=8

Then divide both sides by 5x

X= $\frac{5}{8}$

To solve for y: just use 14y=25+6y

Subtract both sides by 6y

8y=25

Then divide both sides by 8y

y= $\frac{25}{8}$

7 0

2 years ago

you plan to save 600 a month for the next 30 years for retirement. What interest rate would you need to have for 1,000,000 at re

8_murik_8 [283]

Answer:

About 463%

Step-by-step explanation:

600*12= 7200

7200*30= 216000

1,000,000/ 216000 = about 4.63

Check:

4.63*216000= 1,000,080

4 0

3 years ago

-8r –9 > -21...............

Lesechka [4]

Answer:

r < 3/2 or r < 1.5

Step-by-step explanation:

-8r - 9 > 21

-8r > -21 +9

-8r > -12

divide both sides by -8

= r < 3/2 or 1.5

6 0

3 years ago

Each of six jars contains the same number of candies. Alice moves half of the candies from the first jar to the second jar. Then

tino4ka555 [31]

Answer:

The number of candies in the sixth jar is 42.

Step-by-step explanation:

Assume that there are <em>x</em> number of candies in each of the six jars.

⇒ After Alice moves half of the candies from the first jar to the second jar, the number of candies in the second jar is:

$\text{Number of candies in the 2nd jar}=x+\fracx}{2}=\frac{3}{2}x$

⇒ After Boris moves half of the candies from the second jar to the third jar, the number of candies in the third jar is:

$\text{Number of candies in the 3rd jar}=x+\frac{3x}{4}=\frac{7}{4}x$

⇒ After Clara moves half of the candies from the third jar to the fourth jar, the number of candies in the fourth jar is:

$\text{Number of candies in the 4th jar}=x+\frac{7x}{4}=\frac{15}{8}x$

⇒ After Dara moves half of the candies from the fourth jar to the fifth jar, the number of candies in the fifth jar is:

$\text{Number of candies in the 5th jar}=x+\frac{15x}{16}=\frac{31}{16}x$

⇒ After Ed moves half of the candies from the fifth jar to the sixth jar, the number of candies in the sixth jar is:

$\text{Number of candies in the 6th jar}=x+\frac{31x}{32}=\frac{63}{32}x$

Now, it is provided that at the end, 30 candies are in the fourth jar.

Compute the value of <em>x</em> as follows:

$\text{Number of candies in the 4th jar}=40\\\\\frac{15}{8}x=40\\\\x=\frac{40\times 8}{15}\\\\x=\frac{64}{3}$

Compute the number of candies in the sixth jar as follows:

$\text{Number of candies in the 6th jar}=\frac{63}{32}x\\$

$=\frac{63}{32}\times\frac{64}{3}\\\\=21\times2\\\\=42$

Thus, the number of candies in the sixth jar is 42.

4 0

3 years ago

An expression is shown below. Which expression is equivalent to the expression shown?

olya-2409 [2.1K]

Answer:

where's the options

Step-by-step explanation:

i think you made a mistake

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2 years ago

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