Exercise 11 Page 221

The point where the graphs of the equations intersect is the solution of the system of equations.

(- 4,5)

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The solution of the system of linear equations is the point where the graphs of the equations intersect. From the graph, we can tell that this point is (- 4,5).

Let's check this solution by substituting the point into both equations.

6y+3x=18 & (I) - x+4y=24 & (II)

(I), (II):x= - 4, y= 5

6( 5)+3( - 4)? =18 -( - 4)+4( 5)? =24

Multiply

(I):Multiply

30+3(- 4)? =18 -(- 4)+4(5)? =24

MultPosNeg

(I):a(- b)=- a * b

30-12? =18 -(- 4)+4(5)? =24

SubTerm

(I):Subtract term

18=18 -(- 4)+4(5)? =24

Distr

(II):Distribute -1

18=18 4+4(5)? =24

Multiply

(II):Multiply

18=18 4+20? =24

AddTerms

(II):Add terms

18=18 ✓ 24=24 ✓

Since both equations hold true after substituting the point, we know that it is the solution of the system of equations.

Subchapter links

Communicate Your Answer p.217

Monitoring Progress p.218-220

Exercises p.221-222

Exercise 11 Page 221

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