earevalo106 earevalo106

26-05-2015
Mathematics

contestada

2^(2x)+2^(x+2)−12=0
|
Solve for x
Answer

Respuesta :

crisforp crisforp

26-05-2015

2^(2x) = (2^x)^2 ;
2^(x+2) = (2^x) × 4 ;
Let be 2^x = y > 0 ;
y^2 + 4y - 12 = 0 ;
a = 1 ;
b = 4 ;
c = - 12 ;
b^2 - 4ac = 16 + 48 = 64 ;
y1 = ( - 4 + 8 ) / 2 = 2 > 0 ( correct ) ;
y2 = ( - 4 - 8 ) / 2 = - 6 > 0 ( false ) ;
Then, 2^x = 2 ;
x = 1.

Answer Link

Otras preguntas

Which linear function represents the line given by the point-slope equation y – 8 = (x – 4)? f(x) = x + 4 f(x) = x + 6 f(x) = x – 10 f(x) = x – 12

Consider the balanced equation. N2 + 3H2 --> 2NH3 What is the percent yield of NH3 if the reaction of 26.3 g of H2 produces 79.0 g of NH3

_________ wrote “Letters on the equality of the sexes and the condition of women”. a. Angelina Grimke b. Sojourner Truth c. Sarah Grimke d. T.S. Arthur

Ethanol has a density of 0.79g/mL. If a sample has a mass of 10.2 g, what is its volume?

who is riding in the carriage with the speaker in emily dickinson's poem "712" ("because i could not stop for death")? a. the sun b. children c. her husband d.

How would a solution that is labeled 5.0 M would be read as?

Which one of the following sentences is correctly punctuated?. . A. Smile when you say that, Partner?. B. When will the winter end?. C. Look at me, then say

Your friend finally lost those pesky pounds and is showing off a new outfit today. You feel inspired to get healthy yourself. What is this an example of

What is the solution to the system of equations? y = –3x – 2 5x + 2y = 15 (–40, 19) (–19, 55) (19, –40) (55, –19)

what is the theme of Birmingham Sunday by Richard Farina