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
vredina [299]
3 years ago
7

Solve x^2 - 4 = 77.

Mathematics
1 answer:
Gennadij [26K]3 years ago
5 0

Answer:

X = 9 or x = -9

Step-by-step explanation:

We want to solve the quadratic equation

{x}^{2}  - 4 = 77

We shall use the square root method

Let us add 4 to both sides to get:

{x}^{2}  - 4 + 4 = 77 + 4

{x}^{2}  = 81

We take square to get:

x =  \pm \sqrt{81}

x =  \pm9

The solution is x=9 or -9

You might be interested in
If we are given x such that 25^x-9^y=18 and 5^x-3^y=3, compute 5^x+3^y.
leonid [27]

25 = 5*5 and 9 = 3*3, which we can exploit to write

25^x-9^y=(5^2)^x-(3^2)^y=5^{2x}-3^{2y}=(5^x)^2-(3^y)^2

so that this expression is actually a difference of squares. We can factorize this to get

(5^x-3^y)(5^x+3^y)=18

and given that 5^x-3^y=3, we divide both sides by this to get

5^x+3^y=\dfrac{18}3=\boxed{6}

7 0
3 years ago
Otero translated the phrase "three less than a number" into the expression 3 minus x. Which best describes the accuracy of Otero
fomenos

Correct Question:

Otero translated the phrase "three less than a number" into the expression 3 minus x. Which best describes the accuracy of Otero's expression?.

a. It is accurate. The phrase can be translated as "three" = 3, "less than" = subtraction, and "a number" = X, SO 3- X is the correct expression.

b. It is inaccurate. Three is being subtracted from a number, so X-3 is what he should have written.

c. It is inaccurate. Three is being compared to a number, so 3 It is inaccurate. Three is being added to a number, so 3+ x is what he should have written.

Answer:

The answer is B because three less than a number means that a 3 is less than some number X meaning three is being subtracted from X. So equation should be X-3 rather than 3-X.

Step-by-step explanation:

3 0
3 years ago
A pan of brownies is 7/10 full. Tyreese buys 2/5 of the brownies.
elixir [45]

Answer:

The answer to your question is below

Step-by-step explanation:

See the picture, please

In the first picture, we notice the initial amount of brownies (7/10), 7 brownies in a pan for 10 brownies.

After Tyreese bought 2/5   (7/10 - 2/5 = 3/10) there are 3 brownies left.

So in the picture, we notice only 3 brownies in a pan for 3 brownies.

6 0
3 years ago
Find the missing angle in the triangle below
antoniya [11.8K]

Answer:

120

Step-by-step explanation:

Exterior angle theorem

50 + 70 = 120

8 0
3 years ago
Read 2 more answers
Pencils are on sale for $0.99 per dozen. Ms. Klein buys 8 pencils for each of her 96 students. How much will she spend on pencil
defon

Answer:

$63.36

Step-by-step explanation:

First we need to determine how many pencils are needed

8 pencils times 96 students

8*96 =768 pencils

A dozen is 12 pencils

Divide the number of pencils needed by 12 to determine how many dozen pencils are needed

768/12 =64

We need 64 dozen pencils

They cost .99 per dozen

64*.99 =63.36

It will cost $63.36 for  the pencils

3 0
3 years ago
Other questions:
  • You are responsible for maintenance for a fleet of delivery trucks. Truck number 1517 traveled 551.7 miles and used 23.6 gallons
    13·1 answer
  • An entrepreneur is having a design group produce at least eight samples of a new kind of fastener that he wants to market. It co
    13·1 answer
  • Janine wants a necklace 45 beads long 
    11·2 answers
  • What is the solution to the following equation? 5(2x − 14) + 23 = 7x − 14
    14·2 answers
  • Find the median and mean for each data set.
    14·2 answers
  • What is the value of x?​
    7·1 answer
  • Find 121 square by repeated subtraction​
    9·1 answer
  • Which equation represents a linear function that has a slope of g and a y-intercept of -6
    5·1 answer
  • What are the angles in degreees
    7·1 answer
  • Find the cost per roll if a bag of five lunch rolls is $2.50.
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!