1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MAVERICK [17]
3 years ago
9

What is the solution to the system? 1. x-y + 2 z = -7 2. y + z =1 3. x-2 y - 3 z = 0

Mathematics
1 answer:
kvv77 [185]3 years ago
3 0

You'd find this problem easier to understand and do if you'd please list the defining equations vertically and line up variables:

1. x - 1y + 2 z = -7

2. y + 1z = 1

3. x - 2 y - 3 z = 0 Now eliminate the line numbers:

x - 1y + 2 z = -7

1y + 1 z = 1

x - 2 y - 3 z = 0

Let's use the elimination method to eliminate variable z: Seeing that z = 1 - y, we transform the first equation into 1x - 1y + 2(1-y) = -7

and the third into x - 2y - 3(1-y) = 0.

Simplifying 1x - 1y + 2(1-y) = -7

and x - 2y - 3(1-y) = 0,

we get

1x - 2y - 3 + 3y) = 0 and 1x - 1y + 2 - 2y = -7

which in turn simplify to

1x + y = 3 and 1x - 3y = -9

Having eliminated the variable z, we now focus on eliminating x. Mult. the 1st equation by -1, obtaining -1x - 1y = -3. Add this result to 1x - 3y = -9:

0 - 4y = -12, which tells us that y = 3. Subbing 3 for y in 1x + 1y = 3 tells us that x = 0.

All we have left to determine is the vaue of z.

Borrowing Equation 3, from above, we get x - 2 y - 3 z = 0, and into this equation we substitute x = 0 and y = 3: 0 -2(3) - 3z = 0.

Thus, -3z = 6, and z = -2.

The solution set is (0, 3, -2). You should check this by substitution.

You might be interested in
Help to solve -7 - 3a = 1 - 4a
Evgesh-ka [11]

Answer:

-7 - 3a = 1 – 4a  

Step one: Add 4a to -3a  

 

-7 + a = 1  

 

Step two: Add 7 to 1  

 

A = 8  

 

You're done! A=8 for this problem!  

 

 

Hopefully this helps! Feel free to mark brainliest!  

6 0
3 years ago
Read 2 more answers
In San Diego the average cost of gas is $4.15 per gallon. If a car has a fuel efficiency of 24 miles per gallon and the owner of
KIM [24]

Answer:

$25.94

Step-by-step explanation:

150 ÷ 24 = 6.25

6.25 × 4.15 = 25.9375

25.94

3 0
3 years ago
IfA=−3n+2 andB=5n−7, what is the value of A−B, in simplest form?
alukav5142 [94]

Answer:

Either -4n or 0n but most likely -4n

4 0
3 years ago
How much is 2 3/4 cup plus 2 3/4 cup
Viefleur [7K]

Answer:

5.5 US cups

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
Express 72 as a product of its prim factor​
kobusy [5.1K]

Answer:

2 x 2 x 2 x 3 x 3 = 72

6 0
3 years ago
Other questions:
  • Using cubes and flats with the number 1,200
    7·1 answer
  • Please help with work
    13·1 answer
  • Indicate in standard form the equation of the line passing through the given point and having the given slope.
    6·1 answer
  • HELP THIS IS A TEST!!<br> ILL GIVE 20 points!!!
    14·1 answer
  • What is 13/20 as a part to part ratio
    7·1 answer
  • It is known that 10% of the calculators shipped from a particular factory are defective. In a random sample of ten calculators,
    15·1 answer
  • 32.3 = 14.8 + 8.4x hellpppppppppppp
    15·2 answers
  • Help me with geometry plzzzzzzzzzzzzzzzzzzzz
    14·2 answers
  • If mÃc=170° Find mLB
    6·1 answer
  • the height of a right angled triangle is 7cm long and hypotenuse is 25cm long.what will be the area of the triangle​
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!