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
sleet_krkn [62]
4 years ago
13

How to solve 4n²-3n-7=0

Mathematics
2 answers:
Travka [436]4 years ago
5 0
4n^2-3n-7=0\\\\\underbrace{(2n)^2-2\cdot2n\cdot\frac{3}{4}+\left(\frac{3}{4}\right)^2}_{(*)}-\left(\frac{3}{4}\right)^2=7\\\\(2n-\frac{3}{4})^2-\frac{9}{16}=7\\\\(2n-\frac{3}{4})^2=7+\frac{9}{16}\\\\(2n-\frac{3}{4})^2=\frac{112}{16}+\frac{9}{16}\\\\(2n-\frac{3}{4})^2=\frac{121}{16}\to2n-\frac{3}{4}=\sqrt\frac{121}{16}\ \vee\ 2n-\frac{3}{4}=-\sqrt\frac{121}{16}

2n=\frac{11}{4}+\frac{3}{4}\ \vee\ 2n=-\frac{11}{4}+\frac{3}{4}\\\\2n=\frac{14}{4}\ \vee\ 2n=-\frac{8}{4}\\\\2n=\frac{7}{2}\ \vee\ 2n=-2\\\\n=\frac{7}{4}\ \vee\ n=-1



(a-b)^2=a^2-2ab+b^2
almond37 [142]4 years ago
4 0
4n^2-3n-7=0\\ \\ a=4, \ \ b=-3 \ \ c=-7\\ \\ \Delta = b^{2}-4ac = (-3)^{2}-4*4* (-7)= 9+112=121

x_{1}=\frac{-b-\sqrt{\Delta }}{2a} =\frac{ 3-\sqrt{ 121}}{2*4}=\frac{ 3-11}{8}= \frac{-8 }{ 8}=-1 \\ \\x_{2}=\frac{-b+\sqrt{\Delta }}{2a} =\frac{ 3+\sqrt{ 121}}{2*4}=\frac{ 3+11}{8}= \frac{14 }{ 8}= \frac{7}{4}=1\frac{3}{4}


You might be interested in
please help I have no idea on how to do this please help​ I will give a brainlyist to the first person to answer
Julli [10]
Cutting to the chase, the answer is more than 1 kilometer, up to 1,715 meters. If the speed of sound is 343 meters per second then 343 * 5 = 1,715 meters every 5 seconds
8 0
3 years ago
Which system of equations can be used to solve the following problem?
Romashka-Z-Leto [24]
<span>a.2c+6a=148 a+c=38

this is the answer</span>
6 0
3 years ago
Read 2 more answers
What is the equivalent expession of 24x-78y
pickupchik [31]
When you find the GCF (Greatest Common Factor), which is 6 you simplify both by 6 and get 4x-13y
6 0
3 years ago
Round 6.677 to the nearest tenth,
Anon25 [30]

Answer:

6.8

.................

7 0
3 years ago
Read 2 more answers
Which of the following proportions could be used to convert 3600 feet into miles
MA_775_DIABLO [31]

Answer:

Go with the 2nd choice.

Step-by-step explanation:

When using proportions to solve for unknown quantities, you need to keep the same units on the same side. This means keep "ft" on the top side and "mi" on the bottom side.

6 0
4 years ago
Other questions:
  • Help im not sure how to do this
    6·1 answer
  • Don draws one card replaces it and draws another card is it more likely that she draws to red cards or two face cards
    13·1 answer
  • When will the horizontal asymptote alwys be y=0
    12·1 answer
  • A person who weighs 100 pounds on earth weighs 16.6 Ib on the moon
    10·1 answer
  • At a ski resort, 1/4 of the 300 skiers are beginners,and 1/4 of the 260 snowboarders are beginners.The resort staff used the dis
    8·1 answer
  • Corrine wrote temperatures in degrees Celsius and the equivalent temperatures in degrees Fahrenheit. Equivalent Temperatures Cel
    8·2 answers
  • HELP!!!!!<br> .<br> .<br> .<br> .<br> .<br> .<br> .<br> PLEASE
    6·1 answer
  • Lin and Clare were standing in the woods near a stream, and each threw a stone up in the air at the same time so that it would l
    9·1 answer
  • What is the LCD for the given equation? 1/v^2=1/3v-2/v^2
    10·1 answer
  • A) Write 2350 million in standard form.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!