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41 votes
41 votes
Solving by elimination
7x-y=19
2x-3y=19​

User ChumbiChubaGo
by
2.5k points

2 Answers

15 votes
15 votes

Answer:

x=2 and y=−5

Explanation:

Let's solve your system by elimination.

7x−y=19;2x−3y=19

Multiply the first equation by -3,and multiply the second equation by 1.

−3(7x−y=19)

1(2x−3y=19)

Becomes:

−21x+3y=−57

2x−3y=19

Add these equations to eliminate y:

−19x=−38

Then solve−19x=−38for x:

−19x=−38

(Divide both sides by -19)

x=2

Now that we've found x let's plug it back in to solve for y.

Write down an original equation:

7x−y=19

Substitute2forxin7x−y=19:

(7)(2)−y=19

−y+14=19(Simplify both sides of the equation)

−y+14+−14=19+−14(Add -14 to both sides)

−y=5

y=-5

User Stackinfostack
by
3.1k points
11 votes
11 votes

Answer:

2x + y = -2, x + 2y = 2

4x + y - 2z = 0, 2x+ 3z = 9 , -6x - 2y + z = 0

x + y = 4 , x - y = 2

Explanation:

User Luke Cowell
by
2.8k points