Step-by-step explanation:
x+3y=-4(eqn1)
x=-4-3y
from (eqn 2)
2(-4-3y)+6y=5
-8-6y+6y=5
y=5+8=13.
y=13
from eqn 1
x+3(13)=-4
x+39=-4
x=-4-39
x=-43.
Answer:
Index fossil, any animal or plant preserved in the rock record of the Earth that is characteristic of a particular span of geologic time or environment. A useful index fossil must be distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time.
Step-by-step explanation:
The bird watcher saw 7 blue Jays?
Answer:
13.) 314.2 in²
15.) 181.5 ft²
Step-by-step explanation:
The area of a circle is found using the equation:
A = πr²
In this equation, "π" represents the number pi (3.14....) and "r" represents the radius (half the diameter).
For 13.), you have been given the radius. Thus, you can substitute it into the equation and solve for "A".
A = πr²
A = π(10)²
A = π x (100)
A = 314.2 in²
For 15.), you have been given the diameter. To find the radius, you need to divide this value by 2. Once you find the radius, you can plug it into the equation and simplify like above.
diameter = 15.2 ft
radius = 7.6 ft
A = πr²
A = π(7.6)²
A = π x (57.76)
A = 181.5 ft²
