Answer:
y=7
Step-by-step explanation:
We have two numbers,
x
,
y
. We know two things about them:
2
x
+
y
=
25
3
x
−
y
=
20
Let's add these two equations together which will cancel the
y
:
5
x
+
0
y
=
45
x
=
45
5
=
9
We can now substitute in the
x
value into one of the original equations (I'll do both) to get to
y
:
2
x
+
y
=
25
2
(
9
)
+
y
=
25
18
+
y
=
25
y
=
7
3
x
−
y
=
20
3
(
9
)
−
y
=
20
27
−
y
=
20