# Math

posted by Ma names Jeff

17) solve this linear system using the method of substitution.
2y-x=-10
y= -3/2x-1

20) simplify then solve by substitution
2(x-4)+y=6
3x-2(y-3)=13

just need help with these 2.

1. Damon

y= -3/2x-1
which I assume means
y = -(3/2)x - 1
so use that

2 [ -(3/2)x - 1 ] - x = -10

-3 x - 2 - x = -10

-4 x = -8

x = 2 etc

2. Damon

2(x-4)+y=6
3x-2(y-3)=13

2 x - 8 + y = 6
3 x - 2 y + 6 = 13

2 x + y = 14
3 x -2y = 7

y = 14 - 2x use that

3 x - 2 (14-2x) = 7
3 x - 28 + 4 x = 7

7 x = 35 = 7*5
so
x = 5
go back and find y

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