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Alla [95]
3 years ago
14

How to solve x+7y=0 2x-8y=20

Mathematics
1 answer:
photoshop1234 [79]3 years ago
8 0
Solve the following system:
{x + 7 y = 0 | (equation 1)
{2 x - 8 y = 20 | (equation 2)


Swap equation 1 with equation 2:
{2 x - 8 y = 20 | (equation 1)
{x + 7 y = 0 | (equation 2)


Subtract 1/2 × (equation 1) from equation 2:
{2 x - 8 y = 20 | (equation 1)
{0 x+11 y = -10 | (equation 2)

Divide equation 1 by 2:
{x - 4 y = 10 | (equation 1)
{0 x+11 y = -10 | (equation 2)

Divide equation 2 by 11:
{x - 4 y = 10 | (equation 1)
{0 x+y = (-10)/11 | (equation 2)

Add 4 × (equation 2) to equation 1:
{x+0 y = 70/11 | (equation 1)
{0 x+y = -10/11 | (equation 2)
Collect results:
Answer:  {x = 70/11
                {y = -10/11
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Answer:

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3 0
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A savings account earns 7.2 (APR) compounded monthly, so it earns 0.6% each month. Cooper has $1500 in the account now. if he de
iragen [17]

<u>Answer-</u>

<em>Cooper will receive </em><em>$12.00</em><em> at the end of the month.</em>

<u>Solution-</u>

Cooper has $1500 in the account now and he deposits an additional $500 at the beginning of the month.

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But as we have to calculate the monthly interest, so monthly interest rate would be =\dfrac{7.2}{12}=0.6\%

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Therefore, Cooper will receive $12.00 at the end of the month.

7 0
3 years ago
Read 2 more answers
Use the function below to find F(1).<br> F(t) = 2•1/2^3t
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Answer:

D) 1/4

Step-by-step explanation:

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Now we need to figure out what the exponent is that 2 will be raised to. To find that, find out what 3 times one is.

2*1/2^3

Now we need to solve the exponent.

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Remember, 2 cubed is eight.

Now we need to find out what 2*1/8 is. To solve this more easily, I am going to turn two into a fraction. This will give us 2/1*1/8. Now we cross multiply, multiplying the numerators by the numerators, and the denominators by the denominators. Remember, the numerator is the top number, and the denominator is the bottom number.

If we do that, we get:

2/8

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steposvetlana [31]

Answer:

A system of linear equation could only have 1 solution. This is because the straight lines will only have to meet, cross, or intersect each other once.

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There are many different methods in arriving to the final answer. However, errors cannot be perfectly avoided. One of these errors to mistakenly identify equations as linear. It is important that we know that the equations we are dealing with are of exact or correct  characteristics.

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