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
DIA [1.3K]
3 years ago
12

Factor then solve.1.81 - 4x²=02. 4s² + 9 = 12s

Mathematics
2 answers:
elena-14-01-66 [18.8K]3 years ago
7 0
1.\\81-4x^2=0\\\\9^2-(2x)^2=0\\\\(9-2x)(9+2x)=0\iff9-2x=0\ \vee\ 9+2x=0\\\\-2x=-9\ \vee\ 2x=-9\\\\x=4.5\ \vee\ x=-4.5

=============================================================

2.\\4s^2+9=12s\\\\4s^2-12s+9=0\\\\(2s)^2-2\cdot2s\cdot3+3^2=0\\\\(2s-3)^2=0\\\\(2s-3)(2s-3)=0\iff2s-3=0\\\\2s=3\\\\s=1.5
Thepotemich [5.8K]3 years ago
4 0
1.)\ \ \ 81 - 4x^2=0\\\\9^2-(2x)^2=0\ \ \ \ \ and\ \ \ \ \ a^2-b^2=(a-b)(a+b)\\\\(9-2x)(9+2x)=0\ \ \ \Leftrightarrow\ \ \ 9-2x=0\ \ \ or\ \ \ 9+2x=0 \\\\9-2x=0\ \ \ \Leftrightarrow\ \ \ -2x=-9\ \ \ \Leftrightarrow\ \ \ x=4.5\\\\9+2x=0 \ \ \ \Leftrightarrow\ \ \ 2x=-9\ \ \ \Leftrightarrow\ \ \ x=-4.5\\\\.......................................................................\\\\

2.)\ \ \  4s^2+ 9 = 12s\\\\4s^2-12s+ 9 =0\\\\(2s)^2-2\cdot2s\cdot3+3^2=0\\\\(2s-3)^2=0\ \ \ \Leftrightarrow\ \ \ 2s-3=0\ \ \ \Leftrightarrow\ \ \ 2s=3\ \ \ \Leftrightarrow\ \ \ s=1.5
You might be interested in
8x-7y-(3-6y)<br> Simplify each expression
castortr0y [4]
8x - 7y - (3 - 6y) =
8x - 7y - 3 + 6y =
8x - y - 3
7 0
4 years ago
Suppose that the mean systolic blood pressure for women over age seventy is 134 mmHg (millimeters of mercury), with a standard d
IceJOKER [234]

Answer:

See below for answers (in bold) and explanations

Step-by-step explanation:

<u>Part A</u>

According to the Empirical Rule, 99.7% of the data in a normal distribution are ±3σ standard deviations away from the mean. Hence, approximately 99.7% of women over seventy have blood pressures between 134-3σ = 134-3(7) = 134-21 = 113 mmHg and 134+3σ = 134+3(7) = 134+21 = 155 mmHg.

<u>Part B</u>

As 141-134=134-127=7, this represents ±1σ standard deviations away from the mean of 134 mmHg, which corresponds to 68% of the data by the Empirical Rule. Hence, approximately 68% of women over seventy have blood pressures between 127 mmHg and 141 mmHg

4 0
2 years ago
a 10-kg object traveling at 6 m/s collides head on with a 2-kg object at rest. What is the total momentum of the system after th
Neko [114]

Answer:

M1V1i+M2V2i=(M1 + M2)vf

(10)(6)+(2)(0)=(10+2)vf

60=12vf

60÷12 =12vf÷12

5=vf

::Vf=5ms-1 to the right

7 0
3 years ago
Which graph represents the inequality y&lt;−1+2x?
tatiyna
The inequality is y<2x-1.

To draw the solutions, we first start our solution by drawing the line y=2x-1.

To draw a line, it is enough to determine 2 solutions (x, y), plot them in the coordinate axes, and finally join them by a line.

Let x=0, then y=2*0-1=0-1=-1, so we have the point (0, -1).

Now, if y=0, x=1/2, so we have the point (1/2, 0).

We can see that these 2 points are points of the lines on the 2 pictures on the left. Now we want to determine which region to color, the region below the line, or the one above it.

Consider any point which is not on the line, for example (1, 2). We plug x=1 and y=2 in the inequality. If the inequality holds, it means that we are in the solutions region. If it does not hold, then we are on the not solutions regions.

We check: for x=1, y=2 the inequality y<2x-1 is 2<1, which is not true. So the point (1, 2) can't be in the colored region.

Thus the answer is bottom left.

Answer: Bottom left picture.
7 0
3 years ago
Someone help me do this question step by step please? ASAP
boyakko [2]
The answer is 3 hope this helps pls thank me





7 0
3 years ago
Other questions:
  • One number is 11 less than the other number. If their sum is increased by 8 , the result is 71 . Find the numbers.
    12·1 answer
  • Equivalent fraction for 12/15
    10·2 answers
  • Find the value of the expression below.<br>15 + 5 x3<br>3^2+6​
    8·1 answer
  • the model represents the factorization of 2x2+5x+3. what are the factors of the polynomial.(2x+3)(x+1),(2x-3)(x-1),(3x+2)(x-1),(
    10·2 answers
  • The perimeter of a rectangular wooden deck is 90 feet the decks length l is 5 feet less than 4 times it's with, w. Find the leng
    15·1 answer
  • What is 0.36¯¯¯¯ expressed as a fraction in simplest form
    13·2 answers
  • Need help real quick lol pls
    7·1 answer
  • What is the area of the pentagon, rounded to the nearest tenth?
    6·1 answer
  • I need help with the question
    13·1 answer
  • In ΔDEF, the measure of ∠F=90°, DF = 55, FE = 48, and ED = 73. What ratio represents the tangent of ∠D?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!