PEMDAS
Multiplication: 2 + 5 - 18=
Addition: 7-18=
Subtraction: -11
Answer=-11
Answer:
x = 3 ± 2
Step-by-step explanation:
given
x² - 6x + 1 = 0 ( subtract 1 from both sides )
x² - 6x = - 1
To complete the square
add (half the coefficient of the x- term)² to both sides
x² - 6x + (- 3)² = - 1 + (- 3)²
x² - 6x + 9 = - 1 + 9
(x - 3)² = 8 ( take the square root of both sides )
x - 3 = ± 
= ± 2 ( add 3 to both sides )
x = 3 ± 2
Answer: Yes, the point (3,4) is a solution to the system.
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Proof of this:
Replace x with 3 and y with 4 in the first equation
x+y = 7
3+4 = 7
7 = 7
This confirms the first equation. Repeat for the second equation
x-2y = -5
3-2(4) = -5
3 - 8 = -5
-5 = -5
We get true equations for both when we plug in (x,y) = (3,4). This confirms it is a valid solution to the system of equations. It turns out it's the only solution to this system of equations. Visually, the two lines cross at the single location (3,4).
