9514 1404 393
Answer:
obtuse
Step-by-step explanation:
The law of cosines tells you ...
b² = a² +c² -2ac·cos(B)
Substituting for a²+c² using the given equation, we have ...
b² = b²·cos(B)² -2ac·cos(B)
We can subtract b² to get a quadratic in standard form for cos(B).
b²·cos(B)² -2ac·cos(B) -b² = 0
Solving this using the quadratic formula gives ...
The fraction ac/b² is always positive, so the term on the right (the square root) is always greater than 1. The value of cos(B) cannot be greater than 1, so the only viable value for cos(B) is ...
The value of the radical is necessarily greater than ac/b², so cos(B) is necessarily negative. When cos(B) < 0, B > 90°. The triangle is obtuse.
(-3,3) it should be the answer since it is the mean of the both x and y
Answer:
12
Step-by-step explanation:
You set up cross multiplication 3/4 x 9/x, you go 4x9=36 divided by 3 equals 12
First we need to figure out the circumference of the gardening area. The circumference fell is the length around the circle. We can use the circumference formula:
2*pi*r or pi*d
Where r = radius and d=diameter
If you plug in the diameter of 18 ft you get:
18 * pi
= 56.55 ft
Since he can only buy whole foot amounts, we will round up to 57 ft, not down, because he can have a little extra, but can't be under the amount he needs.
Now if it cost $1.50 for every foot, we just multiply that by our footing
1.5 * 57 = $85.50