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]
2 years ago
7

Solve x^2 - 4 = 77.

Mathematics
1 answer:
Gennadij [26K]2 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
The width of a rectangle is 6 and two-thirds inches. The length of the rectangle is twice is width. What is the perimeter of the
Anna007 [38]
P = 2 x ( W+L)
P = 2 x (W + 2W)
p = 2 x 3W
P = 2 x 3(20/3) =40
3 0
2 years ago
I am having trouble learning how to convert an equation to standard form can someone please explain this to me? ( my teacher ten
Molodets [167]
First, you have to simplify the equation:
y+3 = 3(x+5)
y+3=3x+15
So you multiply what’s inside the brackets (x+5) by the factor (3). So 3•x=3x, 3•5=15.
Then you rearrange the equation as necessary to convert it into standard form, which is Ax + By = C
3 0
2 years ago
Which expression is equivalent to the given expression? 17x−32x A. x(32−17) B. 17(x−32) C. 17x(1−32) D. x(17−32)
Olegator [25]
D is correct
good luck
6 0
2 years ago
Read 2 more answers
It has been said that newspapers are disappearing, replaced by various electronic media. In 2004, newspaper circulation (the num
shutvik [7]

Answer:

A. y=-1.2x+59

B. 42.2 million

Step-by-step explanation:

Part A:

Given:

Newspapers circulated in year 2004, y_{1}=59\textrm{ million}

Newspapers circulated in year 2014, y_{2}=47\textrm{ million}

Let the time x start at the year 2004. So, x_{1}=0

For the year 2014, x_{2}=2014-2004=10

Therefore, linear relationship between newspapers circulated and time passed since 2004 is given as:

y-y_{1}=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}(x-x_{1})\\y-59=\frac{47-59}{10-0}(x-0)\\y-59=-\frac{12}{10}x\\y=-1.2x+59

Therefore, the equation describing the relationship is: y=-1.2x+59

Part B:

For the year 2018, x=2018-2004=14

Plug in 14 for x in the above equation and solve for y. This gives,

y=-1.2(14)+59\\y=-16.8+59\\y=42.2

Therefore, in the year 2018, the newspaper circulation will be 42.2 million.

8 0
2 years ago
Use the figure below to find the distance across the river (IK)
Black_prince [1.1K]
<h2>JK = 18m</h2><h2>_______________</h2>

<u>Step-by-step explanation:</u>

ΔJLK = ΔNLM ( <em>v</em><em>e</em><em>r</em><em>t</em><em>i</em><em>c</em><em>a</em><em>l</em><em>l</em><em>y</em><em> </em><em>o</em><em>p</em><em>p</em><em>o</em><em>s</em><em>i</em><em>t</em><em>e</em><em> </em>Δ)

ΔJKL = ΔNML ( <em>e</em><em>a</em><em>c</em><em>h</em><em> </em><em>9</em><em>0</em><em>°</em><em> </em><em>)</em>

so,

triangle JKL = triangle NML (<em>b</em><em>y</em><em> </em><em>A</em><em>A</em><em> </em><em>s</em><em>i</em><em>m</em><em>i</em><em>l</em><em>a</em><em>r</em><em>i</em><em>t</em><em>y</em><em>)</em>

JK / KL = NM / ML

JK / 21m = 42m / 49m

JK = 42 × 21 ÷ 49

JK = 18m

<h2>_______________</h2><h2>FOLLOW ME</h2>
3 0
3 years ago
Other questions:
  • What is the best order-of-magnitude estimate for 789,000?
    8·1 answer
  • Help please just answer these two please.
    6·1 answer
  • Please help ASAP!!! Thanks! :)<br> (−3)(a+x), if a=8, x=−10
    5·2 answers
  • Find the value of the variable and GH if H is between G and I. GI=5b+2,HI=4b-5, HI=3​
    13·1 answer
  • Compare the values of the underlined digits ..<br> 2,783 and 7,283
    8·1 answer
  • Find the slope of the line y=5x+4
    5·2 answers
  • Plz help with any problems you can, show work for number 29
    11·1 answer
  • The diameter of a hula hoop is 24 inches. How many full rotations will the hula hoop make if it travels 528 inches?
    15·1 answer
  • What is the value of x?
    9·1 answer
  • Elizabeth bought lemons (l) and apples (a). Each apple costs 35¢ and each lemon costs 15¢. All together, she bought 17 lemons an
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!