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4 votes
Solve using elimination.

-7x – 5y = 5
-9x – 5y = 15

User JAHelia
by
8.2k points

2 Answers

4 votes
eliminate y's
multiply 2nd eqution by -1 and add to 2nd

-7x-5y=5
9x+5y=-15 +
2x+0y=-10

2x=-10
divide 2
x=-5
sub back

-9x-5y=15
-9(-5)-5y=15
45-5y=15
minus 45 bot sides
-5y=-30
divide both sides by -5
y=6

x=-5
y=6

(x,y)
(-5,6)
User Herr Kater
by
8.0k points
2 votes
-7x-5y=5
-(-9x-5y)=15 It's minus because negative times negative = positive
2x=-10
x= -5

-7(-5) - 5y = 5
35-5y =5
-5y = -30
y=6
User Jubal
by
7.7k points