Answer:
First option: 
Second option: 
Fourth option: 
Step-by-step explanation:
Rewrite each equation in the form 
and then use the Discriminant formula for each equation. This is:
1) For :
Then:
Since 
this equation has no real solutions, but has two complex solutions.
2) For :
Then:
Since this equation has no real solutions, but has two complex solutions.
3) For 
:
Then:
Since 
this equation has one real solution.
4) For :
Then:
Since , this equation has no real solutions, but has two complex solutions.
Answer:
9.9 millimeters
Step-by-step explanation:
To find the perimeter of a square,
Equation: 4 • length = P
So in this case, we're just working backwards. To find the length, divide.
39.6/4 = 9.9
Lucas equation for his location is x(t) = 13t.
Alfonso's equation is x(t) = 238 - 21t
If you equate these, you get:
13t = 238 - 21t =>
34t = 238
t = 7
So after seven hours they meet.
Answer:
1) 20% change I think its an increase.
If needed I could try to answer the 2nd question but I am sure that I got the first one right.
Step-by-step explanation:
By "y = −9x2 − 2x" I assume you meant <span>y = −9x^2 − 2x (the "^" symbol represents exponentiation).
Let's find the first derivative of y with respect to x: dy/dx = -18x - 2. This is equivalent to the slope of the tangent line to the (parabolic) curve. Now let this derivative (slope) = 0 and solve for the critical value: -18x - 2 = 0, or
-18x = 2. Solving for x, x = -2/18, or x = -1/9.
When x = -1/9, y = -9(-1/9)^2 - 2(-1/9). This simplifies to y = -9/9 + 2/9, or
y = -7/9.
The only point at which the tangent to the curve is horiz. is (-1/9,-7/9).</span>
