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Solve the following simultaneous equation using elimination or substitution method

Solve the following simultaneous equation using elimination or substitution method-example-1
User Kosmikus
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1 Answer

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Answer:

(15, 10) and (10, 15)

Step-by-step explanation:

The given system of equation is

x + y = 25

xy = 150

To solve the equation, we will use the subtitution method, so first, we need to solve the first equation for y

x + y = 25

x + y - x = 25 - x

x y= 25 - yx

Then, substitute y = 25 - x on the second equation, we get

xy = 150

x(25 - x) = 150

x(25) - x(x) = 150

25x - x² = 150

Now, we can rewrite the equation as

25x = 15 + x²

0 = 150 + x² - 25x

0 = x² - 25x + 150

Therefore, we need to find the values of x that satisfies

x² - 25x + 150 = 0

Now, we need to factorize this equation, so two numbers that multiply to 150 and add to -25 are -15 and -10. Then

(x - 15)(x - 10) = 0

So, the solutions are

x - 15 = 0

x = 15

or

x 10 = 0

x = 10

Then, the values of y are

If x = 15

y = 25 - x

y = 25 - 15

y = 10

If x = 10

y = 25 - x

y = 25 - 10

y = 15

Therefore, the solutions are (15, 10) and (10, 15)

I

User Hunteros
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