Use the addition and subtraction theorem:
sin (A + B) = sin A + cos B
sin (A - B) = sin A - cos B
From there it's just a matter of simplification.
sin A cos B = 1/2 [ sin (A + B) + sin (A - B) ]
sin A cos B = 1/2 [ sin A cos B + cos A sin B + sin (A - B) ]
sin A cos B = 1/2 [ sin A cos B + cos A sin B + sin A cos B - cos A sin B ]
sin A cos B = 1/2 [ 2 sin A cos B ]
sin A cos B = sin A cos B
Find the factors from the roots, then multiply the factors together.
y
=
x
2
−
21
x
+
104
(-1.2,-2.0) and (1.9,2.2) are the best approximations of the solutions to this system.
Option B
<u>Step-by-step explanation:</u>
Here, we have a graph of two functions from which we need to find the approximate value of common solutions. Let's find this:
First look at where we have intersection points, In first quadrant & in third quadrant.
<u>At first quadrant:</u>
Draw perpendicular lines from x-axis & y-axis from this point . After doing this we can clearly see that the perpendicular lines cut x-axis at x=1.9 and y-axis at y=2.2. So, one point is (1.9,2.2)
<u>At Third quadrant:</u>
Draw perpendicular lines from x-axis & y-axis from this point. After doing this we can clearly see that the perpendicular lines cut x-axis at x=-1.2 and y-axis at y= -2.0. So, other point is (-1.2,-2.0).
<span>A. 30 ft
The formula for the area of a rectangle is width x length = area. Knowing this formula, we can solve for the length by dividing the area by the width. 600 divided by 20 is 30.</span>
