126k views
0 votes
5) x - 4y = 28
-4x - y = 7
Solve each system by elimination

User BrunoLevy
by
8.3k points

2 Answers

5 votes

Answer:

(0,-7)

Explanation:

x-4y=28 multiply by 4

-4x-y=7 multiply by 1

4x-16y=112

-4x-y=7

cross out the x and add the rest

-17y= 119

divide by -17

y= -7

now you substitute the y in one of the equations.

the reformed equations

we will use the second one

-4x-(-7)=7

two negative becomes a plus

-4x+7=7

now you minus the 7 to both sides

-4x=0

now divide by -4

x=0

(0,-7)

User MayaGans
by
7.1k points
2 votes

Answer:

x = 0, y = -7

Explanation:

x - 4y = 28

-4x - y = 7

____________

x - 4y = 28

-16x - 4y = 28

____________ _

17x = 0

x = 0

0 - 4y = 28

y = -7

User Yean
by
7.8k 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