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.
A body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.
1) add.
for example -1 + -2 = - (||-1| + |-2||), which is -(1+2) or -3
2) subtract
for example 4 + -7 = -(||-7| + |4||), which is - |7 - 4| or -3
3) change
for example 3 - (- 2) = 3 + 2
4) -10
the sum is -10.25, which is closest to -10
Answer:
55 =x
Step-by-step explanation:
x+15=2x-40
Subtract x from each side
x-x+15=2x-x-40
15 = x-40
Add 40 to each side
15+40 = x-40+40
55 =x
Step-by-step explanation:
Abby’s Expression:
Double m, giving 2m. She then takes 20% of the result, which we can write 0.2(2m). Finally she subtracts this from 2m, giving 2m−(0.2)2m
2m − (0.2)2m
Renato’s Expression:
Divide m by 5, giving m ÷ 5 = m/5, and then multiplies the result by 8, giving:
8(m/5)