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Solve the system of equations by substitution. show all the steps needed to solve.

2x+3y=19
y=9



3x+9y=42
y=2x



2x + 5y=22
x=3y




x=2y
3x + 2y=2



x+3y=11
x+4y=14

2 Answers

12 votes
Just type all of these in Desmos graphing calculator
User Viktor Bahtev
by
4.3k points
14 votes
2x+3(9)=19
2x+27=19
-27 -27
2x=-8
2x/2=-8/2

x=-4
y=9




3x+9(2x)=42
3x+18x=42
21x=42
21x/21=42/21
x=2
y=2(2)
y=4

x=2
y=4




2(3y)+5y=22
6y+5y=22
11y=22
11y/11=22/11
y=2
x=3(2)

x=6
y=2




3(2y)+2y=2
6y+2y=2
8y=2
8y/8=2/8
y=0.25 or 1/4
x=2(0.25)
x=0.5 or 1/2

x=0.5 or 1/2
y=0.25 or 1/4




x+3y=11
-(x+4y=14)
-1y=-3
-1y/-1=-3/-1
y=3
x+3(3)=11
x+9=11
-9 -9
x=2

x=2
y=3
User Joseph Lust
by
4.4k points