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
il63 [147K]
3 years ago
11

4x - 7y = 3 x - 7y = 15

Mathematics
1 answer:
charle [14.2K]3 years ago
5 0
\left \{ {{4x-7y=3} \atop {x-7y=15}} \right. \\\\
 \left \{ {{4x-7y=3} \atop {x=15+7y}} \right. \\\\ substitution\ method\\\\
4*(15+7y)-7y=3\\\\
60+28y-7y=3\\\\
60+21y=3\ \ \ \ | subtract\ \\\\
21y=-57\\\\
y=-\frac{57}{21}=-\frac{19}{7}\\\\
x=15+7*(-\frac{19}{7})=15-19=-4\\\\\ Solution :\  \left \{ {{y=-\frac{19}{7}} \atop {x=-4}} \right.
You might be interested in
A machine in a factory makes 20 gadgets every 1/4 hour. How many gadgets are made every hour?
Hoochie [10]

Answer:

80 machines

Step-by-step explanation:

If a machine makes 20 gadgets every fourth (1/4) of an hour, it makes 80 machines every hour (20*4).

7 0
3 years ago
I need help finishing a question. I used the explanation function on the program, but it didn't specify what to do to get the fi
leva [86]

I would compute sqrt(1 + 160pi^2) first to get approximately 39.75093337

Add this to 1 and we have 40.75093337

Then divide over 2pi to get a final approximate result of 6.48571248

So x = 6.48571248 is one approximate solution

In short, I computed \frac{1+\sqrt{1+160\pi^2}}{2\pi} only focusing on the plus for now.

----------------------

If you were to compute \frac{1-\sqrt{1+160\pi^2}}{2\pi} you should get roughly -6.167402596 as your other solution. Each solution can then be plugged into the original equation to check if you get 0 or not. You likely won't land exactly on 0 but you'll get close enough.

6 0
3 years ago
Read 2 more answers
Please help me i really need help please
maw [93]

Answer:

39°

Step-by-step explanation:

IM assuming xyz is a triangle

180 - 113 - 28 = 67 - 28 = 39

3 0
3 years ago
Write a quadratic equation with a double root of -5
Sophie [7]

Answer:

x^2 =5

Step-by-step explanation:

8 0
3 years ago
Read 2 more answers
Determine the perimeter and area plzzzz help​
mamaluj [8]

Answer:

The perimeter is 220 , the area should be 100 ,

Step-by-step explanation:The perimeter of the square is 40 because it’s all sides added together & they are all even - The perimeter of a circle is always 360 and this is half of a circle so that is a perimeter of 180; you add that to 40=220. The area is two sides multiplied together=100 for the square. You find the area of the half circle by doing the area of a circle divided by 2.

5 0
3 years ago
Other questions:
  • A polygon with all sides always congruent
    5·2 answers
  • Segment DB is a median of ΔADC. Which statement best describes the relationship between triangles ABD and CBD?
    14·2 answers
  • What is x if 6x-7=13x+8
    15·1 answer
  • Given parallelogram ABCD, diagonals AC and BD intersect at point E. AE=11x−3 and CE=12−4x. Find the length of AC.
    7·1 answer
  • Yvonne had a gross income of $16,800 in 2009. When filing her federal
    9·2 answers
  • Match The Term
    8·2 answers
  • At the bank, Mr Smith changes a £5 note for 20p pieces.<br> How many 20p pieces does he-get?
    6·1 answer
  • Order these numbers from least to greatest 1/5 0.5 0.05 0.23 1/3
    7·1 answer
  • What is 64x12 – 1,000 written as a difference of cubes?
    12·1 answer
  • Evaluate<br> O 15<br> O1<br> What’s the answer?????
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!