Answer:
x = -7
Step-by-step explanation:
To find the value of x, you need to set up a proportion:
= 
Then cross multiply:
15x - 15 = 18x + 36
Then subtract 15x from both sides:
-15 = 3x + 36
Subtract 36 from both sides:
-51 = 3x
Finally, divide both sides by 3:
x = -7
Answer:
Remember that a perfect square trinomial can be factored into the form (a+b)^2
or (a-b)^2
Examples:
(x+2)(x+2) is a perfect sq trinomial --> x^2+4x+4
(x-3)(x-3) is a perfect sq trinomial --> x^2-6x+9
(x+2)(x-3) is not a perfect square trinomial because its not in the form (a+b)^2 or (a-b)^2
Now to answer your question,
for the first one, x^2-16x-64, you cannot factor it so it is not a perfect square trinomial
for the second one, 4x^2 + 12x + 9, you can factor that into (2x+3)(2x+3) = (2x+3)^2 so this is a perfect square trinomial
for the third one, x^2+20x+100 can be factored into (x+10)(x+10) so this is also a perfect square trinomial
for the fourth one, x^2+4x+16 cannot be factored so this is not a perfect square trinomial
Therefore, your answer is choices 2 and 3
Read more on Brainly.com - brainly.com/question/10522355#readmore
Step-by-step explanation:
3.4x3=10.2...
hope this helps!!
Answer:
The answer to your questions is: 25 new teachers
Step-by-step explanation:
Data
# of students = 2000
ratio = 3:80 teachers to students
New teachers = ?
Process
I suggest to use rule of three to solve this problem
3 teachers ---------------- 80 students
x ---------------- 2000 students
x = (2000 x 3) / 80 = 75 teachers
Number of initial teachers = 75
The ratio change to 1:20
1 teacher ------------------- 20 students
x ------------------- 2000 students
x = (2000 x 1) / 20
x = 100 teachers
Number of new teachers = 100 - 75 = 25