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>
2yards= 72 inches
72 inches= 6 feet
so now that you know that, you know that she needs 6 feet and already has 3 feet. so she just needs 3 feet more. but they are asking for the answer to be in inches.
3 feet= 36 inches
your answer in 36 inches
The answer is C.
Step-by-step explanation:
It's C) Ray
Sorry what question? I don’t see anything so I can’t help.
