Answer:
first remove the parentheses on both sides by distributing the multiplication. Then collect all the terms involving
y
on one side (say the left) and the terms without
y
on the right. Finally, divide both sides by the coefficient of
y
. (the number in front of
y
).
It looks like this:
4
(
2
y
−
1
)
=
4
(
y
+
3
)
8
y
−
4
=
4
y
+
12
8
y
−
4
y
=
12
+
4
(subtract
4
y
from both sides and add
4
to both sides)
4
y
=
16
4
y
4
=
16
4
y
=
4
Check your answer.
More thought, looking at the equation:
Instead of distributing the
4
's on both sides, you could start by dividing both sides by
4
(multiplying by
1
4
. This keeps the numbers smaller. It looks like this:
4
(
2
y
−
1
)
=
4
(
y
+
3
)
1
4
[
4
(
2
y
−
1
)
]
=
1
4
[
4
(
y
+
3
]
)
#1/4*4 = [1/4 *4] (y+3)
2
y
−
1
=
y
+
3
2
y
−
y
=
3
+
1
(subtract
y
and add
1
on both sides)
y
=
4
Check your answer.
Answer link
Gió
Mar 25, 2015
First multiply
4
to get rid of the brackets:
8
y
−
4
=
4
y
+
12
Now, isolate the
y
s on one side and numbers on the other of the
=
sign (remembering to change sign in crossing the
=
sign);
8
y
−
4
y
=
+
4
+
12
Notice the change of sign of
4
y
and
−
4
;
now we can add and subtract:
4
y
=
16
The
4
is multiplying the
x
and can go to the right dividing to get:
x
=
16
4
=
4
hope it helps!