Step 1. Combine like terms
Step 2. Subtract 7 from both sides
Step 3. Divide 6 from both sides
Final answer: x=1/6
Step-by-step explanation:
√a is defined only when a >= 0.
Therefore for √4x * √(x + 2) to be defined, both 4x and x + 2 must be non-negative.
When 4x >= 0, x >= 0.
When x + 2 >= 0, x >= -2.
x >= 0 and x >= -2, therefore we have x >= 0. (D)
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>
Answer:
A
Step-by-step explanation:
We take a look at this expression: 
and notice that both terms are square numbers. 
and 
.
There is a specific formula that I highly recommend you memorize involving differences of squares. It states that given the difference of squares 
, it can always be factored into 
.
Here, we can apply that. In this case, a = 7x and b = 3. So:
Thus, the answer is A.
Hope this helps!
Answer:
C=-17
Step-by-step explanation:
-390-52=-442
-442/26=-17
-17
