27.6k views
1 vote
4x-4y=8
5x-3y = 18
Find X

User Martha
by
7.7k points

2 Answers

5 votes
X equals 6

4x-4y=8
+4y +4y
————— << equals
4x=4y+8
—- = —— << divide
4 4
—————- << equals
x=y+2

5x-3y=18
—————
5(y+2)-3y=18
———————- << equals
2y+10=18 << simplified
+-10 +-10
—————- << equals
2y=8
—-=— << divide
2 2
——— <y=4

x=4+2
———- << equals
x=6
User Fergal Moran
by
7.8k points
3 votes

Let's solve your system by substitution.

4x−4y=8 and 5x−3y=18

Step: Solve 4x−4y=8 for x:

4x − 4y = 8

4x − 4y + 4y = 8 + 4y (Add 4y to both sides)

4x = 4y + 8


(4x)/(4) = (4y + 8)/(4)

x = y + 2

Step: Substitute y + 2 for x in 5x − 3y = 18:

5x − 3y = 18

5(y+2) − 3y = 18

2y + 10 = 18 (Simplify both sides of the equation)

2y + 10 + (−10) = 18 + (−10) (Add -10 to both sides)

2y = 8

y = 4

Step: Substitute 4 for y in x = y + 2:

x = y + 2

x=4+2

x=6 (Simplify both sides of the equation)

Answer:

x = 6 and y =4

User Adam James
by
8.5k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories