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Solve the System of equations x = -2 ; y= -3 .(show your work step by step).

x+2y = 4
x +y = 1

User Jozi
by
2.7k points

1 Answer

13 votes
13 votes

Answer:

Determine the point of intersection by using substitution and solving for the variables.

Step-by-step explanation:

Solving a system of equations imply we find the point of interception.

To do this, we must use substitution to find one variable, and use that value to determine the exact value of the other.

Here, we'll isolate

x

.

2

x

2

y

=

4

2

x

=

2

y

4

x

=

y

+

2

Now that we have our variable expression, we can sub this into the other equation and solve for

y

.

2

x

+

3

y

=

9

2

(

y

+

2

)

+

3

y

=

9

2

y

+

4

+

3

y

=

9

4

+

y

=

9

y

=

5

Now that we know our

y

value, we can sub it into any equation to solve for

x

.

x

=

y

+

2

x

=

(

5

)

+

2

x

=

5

+

2

x

=

~

3

Thus, our point of intersection is

(

~

3

,

5

)

.

If we graph the two equations, we can see the point of intersection is in fact

(

~

3

,

5

)

.

graph{(-2x-2y+4)(2x+3y-9)=0 [-8.875, 11.125, -0.36, 9.64]}

Hope this helps :)

User Vicky Chijwani
by
3.0k points
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