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10 votes
Solve the system by substitution.
-4x-y=1
-9x+9=y

User John Lui
by
8.0k points

1 Answer

4 votes

Answer:Add

9

to both sides of the equation.

x

=

y

+

9

x

+

y

=

6

Replace all occurrences of

x

with

y

+

9

in each equation.

Tap for more steps...

2

y

+

9

=

6

x

=

y

+

9

Solve for

y

in the first equation.

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y

=

3

2

x

=

y

+

9

Replace all occurrences of

y

with

3

2

in each equation.

Tap for more steps...

x

=

15

2

y

=

3

2

The solution to the system is the complete set of ordered pairs that are valid solutions.

(

15

2

,

3

2

)

The result can be shown in multiple forms.

Point Form:

(

15

2

,

3

2

)

Equation Form:

x

=

15

2

,

y

=

3

2

image of graph

Explanation:

User Carlossierra
by
7.7k points