V=-2ax+a Exponent 2 on the last a
I think it is 20 seconds because when you multiply six times x, you get twelve. And in this case, the x equals two. So, because you multiplied two to six, you do the same thing to the ten seconds, which is twenty. Sorry if this is the wrong answer.
Answer:

Step-by-step explanation:
To solve for the leg of the missing right triangle, one must use the Pythagorean theorem. The Pythagorean theorem states the following,

Where (a) and (b) are the sides adjacent to or next to the right angle. (c) is the side opposite the right angle. Substitute in the given values and solve for the unknown,

Substitute,

Simplify,

Inverse operations,


Answer: 423.11 m^2
Step by step explanation:
Area of a circle formula pi*r^2
First solve the area of the big circle
3.14*21^2=1384.74 m^2
Now find the are of the smaller circle
r=21-3.5=17.5
3.14*(17.5)^2=961.63 m^2
Now we can minus the small area off the big area to get the shaded area.
1384.74-961.63=423.11 m^2
So the area of the shaded region is 423.11 m^2