To solve problems like this, we must simply break it down and read each part carefully. We can also set it up as a math problem to make it easier to visualize.
The elevator starts on the twentieth floor, so we will represent that with 20.
20
It goes down 11 floors, so we can represent that with a -11.
20-11=9
Now we are on floor 9. Then, we go up 5 floors, so we can represent that with a 5.
9+5=14
Using the math above, we can see the elevator is on the 14th floor.
Answer:
21.
Step-by-step explanation:
f(x) = 2x^2 - 3x + 7.
When x = -2,
f(-2) = 2(-2)^2 - 3(-2) + 7
= 2(4) - (-6) + 7
= 8 + 6 + 7
= 21.
Answer:
x^2 -8x -5 = -3
x^2 -8x -2 = 0
We complete the square by:
1) Moving the "non X" term to the right:
x^2 -8x = 2
2) Dividing the equation by the coefficient of X²
The coefficient of x is 1 so we don't do anything
3) Now here's the "completing the square" stage in which we:
• take the coefficient of X
that is -8
• divide it by 2
-8 ÷ 2 = -4
• square that number
-4*-4 = 16
• then add it to both sides of the equation.
x^2 -8x +16 = 2 +16
That becomes
(x -4)^2 = 18
we take the square root of both sides:
(x -4) = sqr root (18)
x1 = sqr root (18) +4
AND
(x+4) = sqr root (18) -4
x1 = sqr root (18) +4 = 4.2426406871 + 4 = 8.2426406871
x2 = sqr root (18) -4 = = 4.2426406871 - 4 = .2426406871
Step-by-step explanation:
