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
Illusion [34]
3 years ago
15

Solve for k. -21 -3 21

Mathematics
2 answers:
k0ka [10]3 years ago
7 0

Answer:

k = -21

Step-by-step explanation:

9/ (2k-3) = 4/(k+1)

Using cross products

9 * (k+1) = 4(2k-3)

Distribute

9k+9 = 8k -12

Subtract 8k from each side

9k-8k +9 = 8k-8k-12

k+9 = -12

Subtract 9 from each side

k+9-9 = -12-9

k = -21

Nuetrik [128]3 years ago
7 0

Answer:

\huge\boxed{k=21}

Step-by-step explanation:

\dfrac{9}{2k-3}=\dfrac{4}{k+1}

First step:

Find domain.

We know: the denominator must be different than 0.

Therefore we have:

2k-3\neq0\ \wedge\ k+1

2k-3\neq0\qquad\text{add 3 to both sides}\\2k\neq3\qquad\text{divide both sides by 2}\\\boxed{k\neq1.5}\\\\k+1\neq0\qquad\text{subtract 1 from both sides}\\\boxed{k\neq-1}\\\\\text{Domain:}\ x\in\mathbb{R}\backslash\{-1;\ 1.5\}

Second step:

Solve for k.

\dfrac{9}{2k-3}=\dfrac{4}{k+1}\qquad\text{cross multiply}\\\\9(k+1)=4(2k-3)\qquad\text{use the distributive property}:\ a(b+c)=ab+ac\\\\(9)(k)+(9)(1)=(4)(2k)-(4)(3)\\\\9k+9=8k-12\qquad\text{subtract 9 from both sides}\\\\9k=8k-21\qquad\text{subtract}\ 8k\ \text{from both sides}\\\\\boxed{k=21}\in\text{Domain}

You might be interested in
1.Un número complejo multiplicado por su conjugado da siempre:
algol13
B. 2+5i dis the answer
8 0
3 years ago
Read 2 more answers
Simplify fully<br> 8<br> x<br> 12<br> x<br> 2<br> y
Talja [164]

Answer:

8 \times 12 \times 2y = 96 \times 2y = 192y

7 0
3 years ago
R + 12 = 86<br> what does r equal ?
AVprozaik [17]

86 - 12 = 74

74 + 12 = 86

5 0
3 years ago
Read 2 more answers
Pedro bought lb of red sand and lb of brown sand to refill his sand box. Both types of sand cost $4.60 a pound. How much did Ped
Doss [256]
If we know that Pedro bought 1 \frac{1}{4} pounds of red sand, and 5 \frac{1}{2} pounds of brown sand, and they both cost $4.60, then we just have to add the individual amounts of sand, since they cost the same.

1  \frac{1}{4} + 5  \frac{1}{2} = 6  \frac{3}{4}

So Pedro bought 6 \frac{3}{4} lbs of sand overall. Now, we just need to multiply the cost per pound by the total amount of sand he bought.

6 \frac{3}{4} * 4.6 = 31.05

Pedro spent $31.05 on sand, which is answer choice B.
Hope that helped =)
4 0
3 years ago
Read 2 more answers
Which net represents this triangular prism?
Anarel [89]

Answer:

this one.............

3 0
2 years ago
Read 2 more answers
Other questions:
  • A line passes through (2, −1) and (4, 5).<br><br> Which answer is the equation of the line?
    5·1 answer
  • Plz help me!
    12·2 answers
  • Reciprocal of 10 1/2
    13·2 answers
  • Find the coordinates of the midpoint of the segment with the given endpoint S(-1,5) and T(7, -2)
    6·1 answer
  • The factored form of x2 + 3x + 4 is (x + 3)(x + 1)<br> TRUE OR FALSE
    12·2 answers
  • Which best explains why the orthocenter of an obtuse triangle is outside the triangle?
    14·1 answer
  • PLZZZ HELPP 3+7 - 1/2 is an example of A. a numerical equation B. an algebraic equation C. a numerical expression D. an algebrai
    11·1 answer
  • Which of the following are solutions to the quadratic equation x squared plus 8x=9
    15·1 answer
  • *****WILL MARK BRAINLIEST****** help me please 0_o
    11·1 answer
  • Which expression is equal to 48 + 72?
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!