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9x-8y=4
2x-3y=-4
Solving for elimination

2 Answers

3 votes
you could multiply the top equation by 3 and the bottom by -6 so then it would be:
27x-24y=12
-12x+24y=24
you can then get rid of the y since they cancel out each other, so you end up with:
27x=12
-12x=24
combine these two equations so you get:
15x=36
divide both sides by 15 so you get:
x=2.4
then plug x into one of the equations to find y:
2.4-3y=-4
subtract 2.4 from each side
-3y=-6.4
divide both by -3:
y=-2.13
so y=-2.13 and x=2.4
User Menahem Gil
by
7.3k points
3 votes
Use simultaneous equations;

9x - 8y = 4

2x - 3y = -4

We can rearrange the second one to say that:

2x = 3y - 4

x =
(3y-4)/(2)

so;

9(
(3y-4)/(2)) - 8y = 4

9(3y - 4) - 16y = 8

27y - 36 - 16y = 8

11y = 44

y = 4

We then substitute y = 4 back into an original equation

9x - 8y = 4

9x - 8*4 = 4

9x - 32 = 4

9x = 36

x = 4

Final answer;

x = 4, y = 4

User Axel Wolf
by
8.1k points