1.x^2 +6x - 4 = 6x
X^2 + 6x -4 - 6x = 0
X^2 - 4 = 0
By difference of two squares :
X^2 - 4 = 0 can be written as (x-2) (x+2) = 0
(X-2)=0 therefore x= 2
(X+2)=0 therefore x= -2
2. X^2 - 8x = -6x
X^2 -8x + 6x = 0
X^2 - 2x = 0
X(X-2) = 0
X= 0, X= 2
Okie, so percent decrease is the amount loss divided by the original number and multiplied by 100 to find the percent. This is because you are finding the amount loss in terms of the total amount - percent basically.
The amount loss : 4 feet
4 feet/ 12 feet = .3333 (ratio of how much cut) multiply by 100 --> 33.3% decrease. From 12 feet to 8 feet is a 33.3 % decrease. I hope this helps :-)
Answer:
D
Step-by-step explanation:
bc it starts with -square root of 20 and then - square root of 6 and the 3.14 and then square root of 8 and then square root of 18
100*2.2=220
80*2=176
220+176=396
So the two trains will take 2.2 hours so that they are 396 miles apart.
Answer is 5 hope i helped