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Solve by substitution Answer Now

Solve by substitution Answer Now-example-1
User Arben
by
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2 Answers

4 votes
The answer is: (1, 2) .
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Step-by-step explanation:
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Given:

y = 2x ;

y = x + 1; Solve for "x and y" ; Write the solution as an "ordered pair".
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Start with: y = x + 1 ;

Since: y = 2x ; Substitute "2x" for "y" ; in the equation: y = x + 1 ;
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→ 2x = x + 1 ; Subtract "1" ; and subtract "x" ; from each side ;
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→ 2x − 1 − x = x + 1 − 1 - x ;
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→ 1x − 1 = 0 ; ↔ x − 1 = 0 ; Add "1" to each side of the equation ;
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→ x − 1 + 1 = 0 + 1 ;
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to get: → x = 1 .
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Now that we know that " x = 1 " ; we can solve for "y" ; using either (or both!) of 2 (TWO) methods. Let's us both methods — for demonstration purposes—and to confirm that "y" is the same value when "x = 1" (as extra assurance that "x = 0" makes sense!) ;
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1) y = 2x ; so, when "x = 1"; what does "y" equal?

→ Plug in "1" for "x" ; and solve for "y" ;
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→ y = 2*(1) = 2 . So, x = 1; y = 2 .
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2) y = x + 1; so, when "x = 1"; what does "y" equal?

→ Plug in "1" for "x" ; and solve for "y" ;
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→ y = 1 + 1 = 2 . So, x = 1 ; y = 2 .
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→ We write this answer as an "ordered pair"; that is:
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The answer is: (1, 2) .
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User Andrew McKee
by
5.7k points
2 votes
Equation 1) y=2x
Equation 2) y=x + 1

Rearrange the equations so that x and y are on the same side.

1) -2x+y=0
2) -x+y=1

Subtract equations with each other.

Now you have: -x=-1

x=1

Plug in x.

y=2(1)
y=2

(1,2)

~Hope I helped!~
User Abd Abughazaleh
by
5.6k points
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