answer.
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
AVprozaik [17]
2 years ago
14

What is the solution of the system x − 3y = –13 and 5x + 7y = 34? A. `x = (6)/(5)`, y = 4 B. `x = (7)/(2), y = (9)/(2)` C. `x =

(1)/(2), y = (9)/(2)` D. x = –3, y = 7
Mathematics
2 answers:
Masteriza [31]2 years ago
5 0

For this case we have the following system of equations:

x-3y = -13\\5x + 7y = 34

From the first equation we clear "x":

x = -13 + 3y

We substitute in the second equation:

5 (-13 + 3y) + 7y = 34

We apply distributive property:

-65 + 15y + 7y = 34

We add similar terms:

-65 + 22y = 34

We add 65 to both sides:

22y = 34 + 65\\22y = 99

We divide between 22 on both sides:

y = \frac {99} {22}\\y = \frac {9} {2}

We look for the value of the variable "x":

x = -13 + 3 \frac {9} {2}\\x = -13 + \frac {27} {2}\\x = \frac {-26 + 27} {2}\\x = \frac {1} {2}

Thus, the solution of the system is:

(x, y): (\frac {1} {2}, \frac {9} {2})

ANswer:

(x, y): (\frac {1} {2}, \frac {9} {2})

Anna71 [15]2 years ago
4 0

Answer:

C. X=1/2, Y=9/2

Step-by-step explanation:

You might be interested in
-3^(-x)-6=-3^x+10<br><br>Solve the equation below for x by graphing plz
vitfil [10]
To graph it, just graph y=-3^{-x}-6 and y=-3^x+10 and see where they intersect

I would like to solve it by using math and not graphing
if you don't want to see the math, just don't scroll down
the graphical meathod is above, first line, just read it

hmm
multiply both sides by -1
3^{-x}+6=3^x-10
multiply both sides by 3^x
3^0+6(3^x)=3^{2x}-10(3^x)
1+6(3^x)=3^{2x}-10(3^x)
minus 1 from both sides and minus 6(3^x) from both sides
0=3^{2x}-16(3^x)-1
use u subsitution
u=3^x
we can rewrite it as
0=u^2-16u-1
now factor
I mean use quadratic formula
for ax^2+bx+c=0 x=\frac{-b+/-\sqrt{b^2-4ac}}{2a}
so for 0=u^2-16u-1, a=1, b=-16, c=-1
u=\frac{-(-16)+/-\sqrt{(-16)^2-4(1)(-1)}{2(1)}
u=8+/-\sqrt{65}
remember that u=3^x so u>0
if we have u=8+√65, it's fine, but u=8-√65 is negative and not allowed
so therfor
u=8+\sqrt{65}=3^x
8+\sqrt{65}=3^x
if you take the log base 3 of both sides you get
log_3(8+\sqrt{65})=x
if you use ln then
ln(8+\sqrt{65})=xln(3)
then
\frac{ln(8+\sqrt{65})}{ln(3)}=x

8 0
2 years ago
Read 2 more answers
Stefanie is planning a 610-mile trip. Her car’s EPA rating is 34 mpg on the highway. How many gallons of gas will she require fo
agasfer [191]
It going to be 79 mile 
3 0
2 years ago
Which pairs of angles in the figure below are vertical angles?
ch4aika [34]

Answer: Option A and Option C.

Step-by-step explanation:

For this exercise it is important to know the definition of "Vertical Angles".

When two lines intersect or cross, there are a pair of angles that share the same vertex and they are opposite each other. This pair of angles are known as "Vertical angles".

By definition, Vertical angles are congruent, which means that the have the equal measure.

In this case, you can observe in the picture provided in the exercise that the line TI and the line WN intersect each other at the point S.

You can identify that the pair of angles that are opposite to each other and share the same vertex are the shown below:

\angle ISN  and \angle TSW

\angle TSN and \angle ISW

6 0
2 years ago
Bruce wants to make 50 ml of an alcohol solution with a 12% concentration. He has a 10% alcohol solution and a 15% alcohol solut
Daniel [21]
B
Here, x is the volume of the 10ml solution. Multiplying it by its concentration gives the amount of alcohol in it. 50 is the total volume of the 12% solution so (50 - x) gives the volume of the 15% solution. Multiplying this by the concentration gives the amount of alcohol in it. The sum of these amounts of alcohols is equivalent to the amount of alcohol in the 12% solution which is given by the product of its volume and concentration.
5 0
2 years ago
Read 2 more answers
If 300 boxes of medical sponges cost $25.00, how many boxes can you purchase for $0.50?
nikdorinn [45]
You can purchase 6 boxes of medical sponges for $0.50.

Step 1:
Divide 300 by 25.00
300/25= 12
So you get 12 boxes for 1 dollar.
We have 50 cents.

Step 2:
Multiply 12 by 0.50
12*.5 = 6
So you can buy 6 boxes for $0.50.

Hope this helps you! (:
-Hamilton1757
4 0
2 years ago
Read 2 more answers
Other questions:
  • To prove that the triangles are similar by the SAS similarity theorem, it needs to be proven that
    5·2 answers
  • Morgan uses 1/4 of her supply of raisins to make trail mix and 3/8 of her supply of raisins to make cookies. If Morgan uses 5 po
    12·1 answer
  • North lake High school has two lunch periods.... select the true statement
    11·2 answers
  • If a2= 18 and a4= 8, find two possible common ratios. Then, write two sequences lhaving five terms each.
    6·1 answer
  • Witch expression is equivalent to 2.8k - 8.4?
    8·2 answers
  • A research submarine descends 65 meters per minutes to a depth of 4485 m, conducts experiments, and then ascends at a rate of 65
    9·2 answers
  • Brenda created this personal balance sheet. Brenda’s Balance Sheet Assets Liabilities jewelry food wages health insurance commis
    13·1 answer
  • What is the final transformation in the composition of transformations that maps pre-image GHJK to image G'H"J"K"? a translation
    14·2 answers
  • Find the nth term of this sequences<br> 20,18,16,14
    12·2 answers
  • The students at Southern Junior High School are divided into four homerooms. Benjamin just moved into the school district and wi
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!