Actually no scratch that, this is an exact one: -0.1875(x^2+10x+25)+3
The general idea is to use a special operation called the dot product. Given two lists of numbers, where the lists are of equal length, you multiply corresponding elements in each list, then add the products together.
For example, consider the lists {1, 2, 3} and {0, -1, 2}. The dot product of these two lists is 1*0 + 2*(-1) + 3*2 = 0 - 2 + 6 = 4. In matrix form, we would denote this example by

In either case, the orientation of one matrix has to be the opposite of the other, so that the number of rows in the first matrix matches the number of columns in the second matrix.
For matrices of larger size, we can break up the whole product into smaller, 1-row/1-column products like in the example above. For instance, consider the matrix product

The elements in the resulting matrix correspond to the dot products of different combinations of rows from the first matrix and columns from the second matrix. We have

We will see that the solution in the given interval is: x = 0.349 radians.
<h3>How to solve equations with the variable in the argument of a cosine?</h3>
We want to solve:
cos(3*x) = 1/2
Here we must use the inverse cosine function, Acos(x). Remember that:
cos(Acos(x)) = Acos(cos(x)) = x.
If we apply that in both sides, we get:
Acos( cos(3x) ) = Acos(1/2)
3*x = Acos(1/2)
x = Acos(1/2)/3 = 0.349
So x is equal to 0.349 radians, which belongs to the given interval.
If you want to learn more about trigonometry, you can read:
brainly.com/question/8120556
The slope is 2 and the y-intercept is -1