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
krek1111 [17]
3 years ago
14

Follow the directions to solve the system of equations by elimination. 8x + 7y=39 4x – 14y = -68​

Mathematics
1 answer:
harina [27]3 years ago
8 0

Step-by-step explanation:

Hey there!

Here;

The equations are;

8x + 7y = 39.......(i)

4x - 14y =  - 68..........(ii)

Multiplying equation (i) by 2.

16x + 14y = 78

<u>4</u><u>x</u><u> </u><u>-</u><u> </u><u>1</u><u>4</u><u>y</u><u> </u><u> </u><u> </u><u>=</u><u> </u><u>-68</u>

20x = 10

x =  \frac{10}{20}

x = 1/2.

Putting value of 'x' in equation (i).

8 \times  \frac{1}{2}  + 7y =  39

4 + 7y = 39

7y = 3 9 - 4

y =  \frac{35}{7}

Therefore the value of y is 5.

<u>Check</u><u>:</u>

<u>Put</u><u> </u><u>value</u><u> </u><u>of</u><u> </u><u>x</u><u> </u><u>and</u><u> </u><u>y</u><u> </u><u>in</u><u> </u><u>equation</u><u> </u><u>(</u><u>i</u><u>)</u><u>.</u>

8x + 7y = 39

8 \times  \frac{1}{2}  + 7 \times 5 = 39

4 + 35 = 39

39 = 39

(True).

<u>Therefore</u><u>, </u><u>the</u><u> </u><u>solution</u><u> </u><u>is</u><u> </u><u>;</u><u> </u><u>(</u><u>1</u><u>/</u><u>2</u><u>,</u><u>5</u><u>)</u><u>.</u>

<em><u>Hope it helps</u></em><em><u>.</u></em><em><u>.</u></em><em><u>.</u></em>

You might be interested in
Mrs. Alberts has two seventh grade math classes this year. They took their final exam, and Mrs. Alberts just finished grading th
goldfiish [28.3K]

Answer:

these are true = 1, 3, 5

Step-by-step explanation:

overall class a scored better than class b

they're more students in class a compared to class b

7 0
2 years ago
F(1) = 5
MatroZZZ [7]

Answer:

a(7)=3645

Step-by-step explanation:

you have :

f(1) =a= 5

and from recursive rule: f(n) = r · f(n − 1) and f(n) = 3 · f(n − 1)

So r=3

then

a(n)=a*r^(n-1)

a(7)=5*3^(7-1)

a(7)=5*3^6=3645

<em>hope this helps</em>

<em />

7 0
2 years ago
How many solutions are there to the following system of equations?
sweet [91]
4x-8y=0 \\&#10;\underline{-3x+8y=-7} \\&#10;4x-3x=0-7 \\&#10;x=-7 \\ \\&#10;4x-8y=0 \\&#10;4 \times (-7)-8y=0 \\&#10;-28-8y=0 \\&#10;-8y=28 \\&#10;y=\frac{28}{-8} \\&#10;y=-\frac{7}{2} \\ \\&#10; \left \{ {{x=-7} \atop {y=-\frac{7}{2}}} \right.

There is one solution to this system of equations. The answer is B.
6 0
3 years ago
Read 2 more answers
Bobby spent 122 minutes on school work the first week, but only spent 109 minutes on school work the second week.
KengaRu [80]
There is no question to answer here.

but, there is a 13 minute difference in each week
8 0
2 years ago
Read 2 more answers
Help with this question please help
levacccp [35]
Slope is 2
Y intercept is 4
8 0
2 years ago
Other questions:
  • Find the GCF 4x^5y^3+8x^4y^4+4x^3y^2
    9·1 answer
  • PLEASE HELP! WILL MARK BRAINLIEST!
    7·1 answer
  • QUICKKKKKKKK<br> EXPERTS/ACE/TRUSTED HELPERS
    6·1 answer
  • Factor each linear expression.if expression can not be factored write cannot be factored.<br> 36x-9
    10·1 answer
  • A right triangle has one leg with a length of 48 and a hypotenuse with a length of 80. What is the length of the other leg?
    6·2 answers
  • Write an equation of the circle given its center and radius
    12·2 answers
  • Two number cubes are rolled. What is the probability that the first lands on 2 and the second lands on a number greater than 4?
    8·2 answers
  • A ladder leans against the side of a house. The angle of elevation of the ladder is 68° when the bottom of the ladder is 16 it f
    7·1 answer
  • Find the slope of the line through the given pair of points.<br> (-2, 18), (10,3)
    15·1 answer
  • 155.5-5.5∙20.7 help me with this
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!