In this question, it is given that the diagonal of the board is 18 inches long and one side of the board is 12 inches long.
Let the other side is of length b inches .
Now we use pythagorean identity, which is

Here, a = 12 and c=18
Substituting these values, we will get

And the formula of perimeter is

Substituting the values of the two legs, we will get

Answer:
$52.44
Step-by-step explanation:
So here is the explanation. $240•.80= 192 (80% as a decimal is .80) 240-192=48. 48•.0925=4.44 which you add 48, and get a sum of $52.44
Hope this helps :)
Answer:
x = 15
Step-by-step explanation:
Assuming 3x and x-60 are in degrees, you can use:
cos(a) = sin(a+90)
To rewrite the equation as:
sin(3x) = sin(x-60+90)
sin(3x) = sin(x+30)
3x = x+30
2x = 30
x = 15
But, solving 3x = x+30 which simplifies to x=15 is not the only solution to this equation, as you can see in below picture. Finding all solutions is a bit more work, but maybe that is not required in your case.
The solid line indicates that the line itself is included in the solutions. That the shaded area is to the left, or under, the line means that y≤the line.
To find the equation of the line you first find the slope or m using any two points.
m=(y2-y1)/(x2-x1) in this case you are given (2,-5) and (-2, 3) so
m=(3--5)/(-2-2)
m=8/-4
m=-2
So far for y≤mx+b we have:
y=-2x+b using either point we can solve for b, I'll use (2,-5)
-5=-2(2)+b
-5=-4+b
-1=b
So the line is:
y=-2x-1 and since y≤ the line:
y≤-2x-1