A petri dish is simply a circle; thus, we use the formula of the area of the circle which is <span>πr^2.
Given r = 40 mm
A = </span>π(40)^2 = <span>5026.55 sq. mm
</span>
Population density = bacteria count / area
PD = 2,100 / <span>5026.55
PD = </span><span>0.417782 bacteria / mm sq.
Therefore, the answer is approximately 0.418 </span><span>bacteria per square millimeter.</span>
I’m not the best at math, but ⬇️
For example, apply the distributive property to the expression 3(2 + x) to produce the equivalent expression 6 + 3x; apply the distributive property to the expression 24x + 18y to produce the equivalent expression 6 (4x + 3y); apply properties of operations to y + y + y to produce the equivalent expression 3y
Answer:
6/54 or 1/9
Step-by-step explanation:
6/54 reduces to 1/9
hope this helps
Answer:
x=-5 x=-4
Step-by-step explanation:
y=x^2 + 9x + 20
We need to factor the equation
What 2 numbers multiply to 20 and add to 9
4*5 = 20
4+5 =9
y=(x+5) (x+4)
To find the zero's we set the equation equal to zero
0= (x+5) (x+4)
Using the zero product property
x+5 = 0 x+4=0
x=-5 x=-4
Answer:
C.
Step-by-step explanation:
