How do you solve this system of equations using the addition method:
4
x
−
y
=
−
4
;
5
x
+
2
y
=
−
18
?
Algebra
1 Answer
IDKwhatName
Jun 30, 2017
x
=
−
2
,
y
=
−
4
Explanation:
Right now, you have:
4
x
−
y
=
−
4
5
x
+
2
y
=
−
18
To make this easier, you must get rid of one variable, in this case I will remove
y
, to do this you must make the y-values in both equations the same.
To do this, I will multiply the whole of
4
x
−
y
=
−
4
by 2 to give
8
x
−
2
y
=
−
8
We now have:
8
x
−
2
y
=
−
8
5
z
+
2
y
=
−
18
All we need to do now is
(
8
x
−
2
y
+
5
x
+
2
y
)
=
(
−
18
−
8
)
≡
13
x
=
−
26
.
Divide both sides by 13 to find
x
:
13
x
=
−
26
13
x
13
=
−
26
13
x
=
−
2
Now put your value for
x
into either equation:
4
(
−
2
)
−
y
=
−
4
−
8
−
y
=
−
4
y
=
−
8
+
4
y
=
−
4
x
=
−
2
;
y
=
−
4
Answer link
Answer:
um 21
Step-by-step explanation:
Answer:
x = 750
Explanation:
25x = 30
1. Multiply 25 by 30
25 * 30 = 750
2. Divide 750 by 25
750/25 = 30
3. Divide 750 by 30
750/30 = 25
Therefore, x = 750
Answer:
Serina should have solved for x in the second equation because it has a coefficient of 1.
Step-by-step explanation:
we have
----> equation A
---> equation B
we know that
To solve the system of equations in the most efficient way, solve for x equation B and then substitute the value of x in equation A
so
----> equation C
substitute equation C in equation A
solve for y
Find the value of x
substitute the value of y in the equation C
The solution is (3,4)
therefore
Serina should have solved for x in the second equation because it has a coefficient of 1.
Answer:
y=5
Step-by-step explanation:
Get rid of the parenthesis by multiplying
2y=6+4
Add
2y=10
Divide
y=5
