Solve the system of equations: y=2x y=x²-8

1 answer:

6 0

Set equal to each other
x^2 - 8 = 2x
x^2 - 2x - 8 = 0

Factor
(x - 4)(x + 2) = 0
x = 4 or x = -2

Plug in 4
y = 2x or y = x^2 - 8
y = 2(4) or y = 4^2 - 8
y = 8

Plug in -2
y = 2x or y = x^2 - 8
y = 2(-2) or y = (-2)^2 - 8
y = -4

There are two solutions
(4, 8) and (-2, -4)

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Step-by-step explanation:

First thing you gotta do is find the common denominator.

Do this by listing factors of the denominators:

5- 5, 10, 15, 20, 25, 30

6- 6, 12, 18, 24, 30, 36

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What you do to the bottom you must do to the top.

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Since you multiply 6 by 5 to get 30, then multiply 5 by 5 as well.

The new equation is:

$\frac{12}{30}$ + $\frac{25}{30}$ + $\frac{24}{30}$ =

Now add the numerators together

The solution is $\frac{61}{30}$ . Now simplify. 61 is prime, so you cannot change the fraction How many times does 30 go into 61? Two times. This gives us 2 $\frac{1}{30}$ .