mee79
mee79 mee79
  • 02-04-2018
  • Mathematics
contestada

when is 2 x -3 equal to x squared minus 5

Respuesta :

altavistard
altavistard altavistard
  • 02-04-2018
Solve:  2x - 3 = x^2 - 5 (at least, this is my interpretation of your 2 x -3).

x^2 - 5 - 2x + 3 + 0, or x^2 - 2x - 2 = 0

I will solve this by "completing the square:"

x^2 - 2x +(1)^2 - (1)^2 - 2 = 0, or x^2 - 2x + 1 - 1 - 2 = 0

This is    (x-1)^2 = 3.  Taking the sqrt of both sides, we get:

x-1 = plus or minus sqrt(3).  Then x=1+sqrt(3) or x=1-sqrt(3).  These are the two values of x for which  2x - 3 = x^2 - 5 is true.
Answer Link

Otras preguntas

5x+4y+100 in slope intercept form
A farmer hauled in 120 bales of hay. Each of his cows ate 1 1/4 bales. How many cows the farmer feed?
By the mid-1700s, the largest city in the colonies was (A) New York (B) Boston (C) Philadelphia (D) Charleston (E) Wilmington, Delaware
Which of the following statements is true concerning LUCA? (1) LUCA was a cell. (2) All life on Earth evolved from LUCA. (3) LUCA probably existed probably arou
Find the value of x.  Round to nearest hundredth if necessary.
which seismic wave moves through earth at the fastest speed?
How do scientists use seismic waves to determine the interior structure of Earth?
How many atoms are in 0.750 moles of zinc?
Why was is difficult for the Arab people to form one nation?
What is the mean of 87, 93, 86, 90, and 84?