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
Sonja [21]
3 years ago
10

Let x^2+15x=49

Mathematics
2 answers:
-BARSIC- [3]3 years ago
8 0

The correct answer is:

x^2 + 15x + 56.25 = 105.25

i just finished the test and these were the correct answers :)

Slav-nsk [51]3 years ago
3 0
<span>x^2 + 15x + 56.25 = 105.25

    "Completing the square" is one of many different techniques for solving a quadratic equation. What you do is add a constant to both sides of the equation such that the lefthand side can be factored into the form a(x+d)^2. For instance, squaring (X+D) = X^2 + 2DX + D^2. Notice the 2DX term. That is the same term as the 15x term in the problem. So 2D = 15, D = 7.5. And D^2 = 7.5^2 = 56.25.
So we have
 x^2 + 15x + 56.25 = 49 + 56.25
 Which is
 x^2 + 15x + 56.25 = 105.25
  Which is the answer desired.

   Now the rest of this is going beyond the answer. Namely, it's answering the question "Why does complementing the square help?" Well, we know that the left hand side of the equation can now be written as
 (x+7.5)^2 = 105.25

   Now take the square root of each side
 (x+7.5) = sqrt(105.25)

   And let's use both the positive and negative square roots.
So x+7.5 = 10.25914226
 and
 x+7.5 = -10.25914226

   And let's find X.
 x+7.5 = 10.25914226
 x = 2.759142264

   x+7.5 = -10.25914226
 x = -17.75914226

   So the roots for x^2 + 15x - 49 is 2.759142264, and -17.75914226</span>
You might be interested in
If there are four quarters in a dollar, which expression correctly shows how you might figure out how many quarters are in $9.25
xxMikexx [17]

Answer:

37

Step-by-step explanation:

4(9) + 1 = 37

7 0
3 years ago
Read 2 more answers
Hi...I am taking pre calculus and I'm reallyo lost here..can someone help me?
Karolina [17]
1. Log7 (49)=2
2. Log63(216)=3
3. Log2 (256)=8
4. Log4 (64)= 3
5. Log5 (3125)=5
3 0
3 years ago
Answer al 4 question and I’ll give your Brainly
miv72 [106K]

Answer:

C-C-B-D

Step-by-step explanation:

Hope this helps and look out for people trying to take your points!

6 0
3 years ago
Each car in a rental fleet is either red or white, and there are 75 cars total. There are three more white than twice the number
professor190 [17]
Number of red cars = x
Number of white cars = y

x + y = 75
y + 3 = 2x

x + y = 75
y = 75 - x

(75 - x) + 3 = 2x
78 = 3x
26 = x

y + 3 = 2(26)
y + 3 = 52
y = 49

There are 49 white cars.
8 0
3 years ago
Read 2 more answers
Find thea value of x in the following proportion<br>2:5=14:X<br>​
Alona [7]
Answer: x = 35

Explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • Square root of 98k???
    8·1 answer
  • Square root of 50 + square root of 72
    11·2 answers
  • Bella's Pizza Shop charges $4.50 for a small pizza, $7 for a medium pizza, and $9 for a large pizza. Toppings cost extra dependi
    5·1 answer
  • Find the ratio of m to n. 8n = 2m
    5·2 answers
  • What is the equation of the graph below ?
    12·1 answer
  • Please help me the picture is above I really need an answer please, I’ll mark as brainliest
    6·1 answer
  • Please help me i really need help please
    14·1 answer
  • Multiply the fractions. Select the answer that is in simplest form.
    15·1 answer
  • Please help!! graph y=-4/3x+8
    13·1 answer
  • Deondre's baseball team is selling raffle tickets for a fundraiser. It cost them $105 to print the tickets. They set a goal to m
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!