well, we know that θ is in the III Quadrant, where the sine is negative and the cosine is negative as well, or if you wish, where "x" as well as "y" are both negative, now, the hypotenuse or radius of the circle is just a distance amount, so is never negative, so in the equation of cos(θ) = - (2/5), the negative must be the adjacent side, thus


Answer:
12. B
13 A
18 B
19 B
Step-by-step explanation:
12. The solutions of the quadratic is the roots, so 0 = x^2 -7x -30 = (x-10)(x+3). For this to be satisfied, either x-10 = 0 -> x = 10 and x + 3 = 0 -> x = -3
13. Either x = 0 or x+8 = 0 -> x =-8 for this to be true
18. The GCF of 2, 6, and 20 is 2. No other number satisfies being a common factor.
19. The product of the solutions of the equation is the (constant/leading coefficient) in the quadratic, which is -8/1 = -8
I hope this helps! :)
We have an triangle:
base=4 in
height=3 in,
This triangle can be dividided into two equal triangles, we need calculate the hypotenuse.
leg₁=4 in/2=2 in
leg₂=3 in
Pythagoras law:
hypotenuse²=leg₁²+leg₂²
hypotenuse²=(2 in)²+(3 in)²
hypotenuse²=4 in²+9 in²
hypotenuse²=13 in²
hypotenuse=√13 in.
Now, we can find the surface area.
Surface area=2 *(rectangle area)+base area + 2(triangle area)
rectangle area=10 in x √13 in=10√13 in²
base area=10 in x 4 in=40 in²
Triangle area=(4 in x 3 in)/2=6 in²
Surface area=2(10√13 in²)+40 in²+2(6 in²)=(20√13+52) in²≈124.11 in²
Answer: 124.11 in²
The second choice
It has adding on both sides