Let x = your number.
x^2 - 21 = 4x. Subtract 4x from both sides.
x^2 - 4x - 21 = 0. Factor.
(x - 7) (x + 3) = 0. Set each term to 0.
x + 3 = 0. Subtract 3 from both sides.
x = -3. This is the negative solution.
Set the other term equal to zero.
x - 7 = 0. Add 7 to each side.
x = 7. This is the positive solution.
Answer:
A
Step-by-step explanation:
Answers:
1. X= 0
2. X= 0
3. X=3
You can use this method to solve them step by step, hope it will help!
Answer:
18
Step-by-step explanation:
You can see from the table that 2 bracelets are made every 30 minutes.
There are 9 intervals of 30 minutes each in 4.5 hours.
So, the number of bracelets that are made in 4.5 hours is
9x2=18
Another way to see this is to note from the table that 4 bracelets are made in 60 minute, which is 1 hour. So, in 4 hours, 16 bracelets will be made. Also, from the table, 2 bracelets are made in 30 minutes, which is 1/2 hour. So, adding up, 18 bracelets are made in 4.5 hours.
Answer:
D.
Step-by-step explanation:
2y = (2 x y) = 2 x 0 = 0
<em>0 - 0 = 0</em>