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2 votes
2 votes
Is (-2, 0) the solution to the system below?

y = -3x - 6 and 2x + 3y = -15

Circle your final answer. SHOW WORK as mathematical proof.

User JeramyRR
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2 Answers

20 votes
20 votes

(-3/7, -4 5/7)


it tells u what y is so plug that in to the second equation which would give you 2x+3(-3x-6)=-15. simplify that which would give you 2x-9x-18=-15. simplify again which would give u -7x=3. then solve for x which is -3/7. than plug -3/7 in as x which gives you y=-3(-3/7)-6. simplify that which gives you 9/7-6 which equals -4 5/7.
User DaveSav
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2.8k points
23 votes
23 votes

Answer:

No, the answer is (-3/7, -33/7)

Explanation:

y=-3x-6 can be rewritten as y+3x=-6

so, our two equations are:

1. y+3x=-6

2. 3y+2x=-15

we can multiply the first equation by 3.

1-1.3y+9x=-18

Now we can subtract the second equation from equation 1-1.

3y+9x=-18

-(3y+2x=-15)

7x=-3

x=-3/7

Now that we have x, let's plug it into an equation. I will plug it into the first equation.

y=-3(-3/7) - 6

y=9/7 - 6

y=-33/7

so the points are (-3/7, -33/7)

User Clinemi
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2.9k points