Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
Let the number of reptiles on endangered list be 'x'
2x + 16=158
2x=158-16
2x=142
x=71
So there are 71 reptiles on the endangered list
Answer:
3:2
Step-by-step explanation:
Ewen has 48 white tiles and 16 blue tiles
The cost of each white tile was £2
The cost of each blue tile was £4
Therefore the total cost of 48 white tiles is
= 48×2
= £96
The total cost of 16 blue tiles is
= 16×4
= £64
The ratio of the total cost of the white tiles and blue tile can be calculated by dividing the cost of both tiles by their greatest common factor
The greatest common factor of £96 and £64 is 32
96/32 = 3
64/32= 2
Ratio= 3:2
Hence the ratio of the total cost of the white tiles to the blue tiles is 3:2
Probably A, a plane
I hope this helps you! If it does, please rate as Brainliest :D
Answer:
Tito have 
textbooks in terms of x
Step-by-step explanation:
Rudy has 6 textbooks
We are given that Tito and Maria each have y textbooks
So, Tito has no. of books = y
Maria has no. of books = y
So, total number of textbooks = 6+y+y=6+2y
We are given that Rudy, Maria, and Tito have a total of x textbooks
So,6+2y=x
So, 2y=x-6
Hence Tito have textbooks in terms of x
