RuralOregonDeputy RuralOregonDeputy
  • 01-05-2017
  • Mathematics
contestada

QUESTION FOR 50 POINTS
Solve this equation using an algebraic method: (x + 4)(x - 4) = 9
Choices are:
x=5
x=4 and x=-4
x=9
x=5 and x=-5

Respuesta :

irspow
irspow irspow
  • 01-05-2017
(x+4)(x-4)=9  expand left side by performing indicated multiplication...

x^2-16=9 add 16 to both sides

x^2=25  take the square root of both sides...

x=±5

x=-5 and 5

So the answer would be the bottom choice.
Answer Link
phillipino2002
phillipino2002 phillipino2002
  • 01-05-2017
the answer is 
x=5 and x=-5
Answer Link

Otras preguntas

Which has a higher resistance, a 25 W lightbulb or a 50 W bulb?
A deli sandwich is placed inside a cooler
How would you handle a seat dispute between two passengers? a) Choose a favorite passenger b) Encourage both to stand c) Mediate and find a resolution d) Take a
How many officers make up the current Directorate? Listen their names and positions.
Which has a higher resistance, a 25 W lightbulb or a 50 W bulb?
Which equation matches the function shown in the graph? 3-Y 2- 1- 0- B. -E O A. y = 3 sin(x) O C. 27T y = 2 sin (2x) + 1 y = 3 sin (2x) OD. y = 2 sin (x) + 1 3π
What does 5x+6y+1 equal
Each of the 4 elementary schools in the city has 1,875 students. Both middle schools have 3,124 students. The high school has 7,943 students. How many students
ou noticed a mistake: Your own records do not match the bank statement you just received. Which option describes the steps you should take to solve this situat
How should you connect a voltage meter when checking AC voltage?