Answer:
12
Step-by-step explanation:
2/3 x + x = 20
2/3 x + 3/3x = 20
5/3 x = 20 ... times 3/5 both sides
x = 12
check: 2/3 x 12 + 12 = 8 + 12 = 20
You will need almost four cans of paint: 3.8088888888
Answer:
0
Step-by-step explanation:
![\left[\begin{array}{ccc}a&b\\c&d\end{array}\right] = ad-bc](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Da%26b%5C%5Cc%26d%5Cend%7Barray%7D%5Cright%5D%20%3D%20ad-bc)
0(4)-4(0) = 0
The circumference can be obtained fairly easily by simply substituting the d in c = πd for the colony's given diameter of 12 mm. Performing that calculation using the approximation of π ≈ 3.14, we obtain a circumference of 12 x 3.14 = 37.68 mm.
To find the radius, remember how the diameter and radius of a circle are defined. The radius is a length extending from the center of a circle to a point on its circumference, and a diameter is a line extending from one point on the circle's circumference to an opposite point, passing through the circle's center along the way. The diameter can, in this way, be defined as twice the length of the radius, which means we can find the radius of a circle by taking half of its diameter. In this case, our diameter is 12 mm, so our radius would be 6 mm.
There is no solution for the first one
if you eliminate y you get 2 equations
-13x - 13z = -25
-13x - 13x = -15
- there is no solution to theses
a23 means the element in the second row and the 3rd column
so its -5