Answer:
Step-by-step explanation:
F(x) = 7 - 5x + 7x²
f(-9) = 7 - 5*(-9) + 7*(-9)²
= 7 + 45 + 7*81
= 7 + 45 + 567
= 619
Answer:

Step-by-step explanation:
using the rule of exponents
⇔ 
f(- 5) =
=
= 
Answer:
125.6 cm²
Step-by-step explanation:
Area of the shaded region = area of larger circle - area of the smaller circle
Area of the smaller circle = πr²
π = 3.14, r = 3 cm
Area of smaller circle = 3.14*3² = 3.14*9 = 28.26 cm²
Area of larger circle = πr²
π = 3.14, r = 7
Area of larger circle = 3.14*7² = 3.14*49 = 153.86 cm²
Area of the shaded region = 153.86 - 28.26 = 125.6 cm²
Answer:
36 cm
Step-by-step explanation:
The formula to find the area of a triangle is A=1/2bh where b stands for base and h for height.
So, 8 times 9 equals 72, and 72 divided by 2 is 36.
Answer: 80 miles
Step-by-step explanation: