Answer:
x=−1/2
and y=−2/3
Explanation:
Multiply the first equation by 5,and multiply the second equation by 3.
5(4x−9y=4)
3(6x+15y=−13)
Becomes:
20x−45y=20
18x+45y=−39
Add these equations to eliminate y:
38x=−19
Then solve38x=−19for x:
38x=−19
38x
38
=
−19
38
(Divide both sides by 38)
x=
−1
2
Now that we've found x let's plug it back in to solve for y.
Write down an original equation:
4x−9y=4
Substitute
−1
2
forxin4x−9y=4:
4(
−1
2
)−9y=4
−9y−2=4(Simplify both sides of the equation)
−9y−2+2=4+2(Add 2 to both sides)
−9y=6
−9y
−9
=
6
−9
(Divide both sides by -9)
y=
−2
3