The variable is x.
Hope that helps :)
Answer:
length of rectangle = 5
width of rectangle = 5
Area of rectangle = 25
Step-by-step explanation:
Since the length of the rectangle is "x", and the value of the area is given by the product of the length "x" times the width "10-x", indeed, the area "y" of the rectangle is given by the equation:

Now, they tell us that the area of the rectangle is such that coincides with the maximum (vertex) of the parabola this quadratic expression represents. So in order to find the dimensions of the rectangle and therefore its area, we find the x-coordinate for the vertex, and from it, the y-coordinate of the vertex, which is the rectangle's actual area.
Recall that the formula for the x of the vertex of a quadratic of the form :

is given by the formula:

which in our case gives:

Therefore, the length of the rectangle is 5, and its width (10-x) is also 5.
The area of the rectangle is therefore the product of these two values: 5 * 5 = 25
Which should coincide with the value we obtain when we replace x by 5 in the area formula:

Hi there!
To solve this problem, we need to first find the amount of red tiles he used by subtracting 50 from 310, and then finding the sum of the two numbers.
310 - 50 = 260
Now, we know that there are 260 red tiles.
3 * 310 = 930
3 * 260 = 780
930 + 780 = 1710
So, the answer is 1710 tiles total.
Hope this helps!
Answer:
The measure of angle A is 
Step-by-step explanation:
we know that
Applying the law of cosines

substitute the values and solve for cos(A)

![cos(A)=[22^{2}+18^{2}-31^{2}]/(2(22)(18))\\ \\cos(A)=-0.193182\\ \\A=arccos(-0.193182)=101\°](https://tex.z-dn.net/?f=cos%28A%29%3D%5B22%5E%7B2%7D%2B18%5E%7B2%7D-31%5E%7B2%7D%5D%2F%282%2822%29%2818%29%29%5C%5C%20%5C%5Ccos%28A%29%3D-0.193182%5C%5C%20%5C%5CA%3Darccos%28-0.193182%29%3D101%5C%C2%B0)
I think the answer is d hope this helps