Can someone please help me, this is my last question I have been stuck on it for 30 minThe work of a student to solve a set of equations is shown:

Equation A: y = 15 − 2z
Equation B: 2y = 3 − 4z


Step 1: −2(y) = −2(15 − 2z) [Equation A is multiplied by −2.]
2y = 3 − 4z [Equation B]
Step 2: −2y = 15 − 2z [Equation A in Step 1 is simplified.]
2y = 3 − 4z [Equation B]
Step 3: 0 = 18 − 6z [Equations in Step 2 are added.]
Step 4: 6z = 18
Step 5: z = 3


In which step did the student first make an error?
Step1
Step 2
Step 3
Step 4

Answers

Answer 1
Answer: step 2
he didn't distribute
what he did:
-2(15-2z)=15-2z
that is obviously false

what should have happened is
-2(15-2z)=-30+4z
then add

-2y=-30+4z
2y=4-4z
0=-26
false
no solution
inconsitient, these lines ar paralell


anyway, step 2 is error
Answer 2
Answer: The mistake was made in step 2.  In simplifying the equation, he has to distribute the -2 through the parentheses.  Step 2 simplification should be

-2y = -30 + 4z

When the 2 equations are added, the resultant equation is 0 = -27 therefore it has no solution. 

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Answers

Answer:

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hope this helps!

By what fraction name for 1 must 2/3 be multiplied to form a fraction with a denominator of 15

Answers

If you are asking what I think than it should be 5/5 because 3*5=15 so in that case the denominator would be 15 making the whole answer 10/15 although that could still be simplified to 2/3) (that's what happens when you multiply by one) 

Or you may be asking 1/x forms a denominator of 15.
In this case you would still have 5 as your number (or really 1/5), if would just mean when they are multiplied together you would get 2/15 instead....

Help me please >.< ---------------------

Answers

10.

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Samantha builds one birdhouse in 6 3/8 hours. How many hours does it take to build 4 birdhouses?

Answers

6 and 3/4 times 4....

6 times 4 is 24

4 times 3 is 12, so 12 over 4 is equal to 3

And 24 plus 3 is 27, so 27 hours is what i believe the answer shoudl be

Hopefully y'all can help me on this

Answers

Find the area of one triangle ( half base times height ) and times it by the height of the prism. (12x9=) 108m. 108m is your answer.

What happened to the cat who swallowed a ball of yarn?

Answers

the cat who swallowd the yarn died
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