Answer:
Step-by-step explanation:
The formula of an area of a circle:
r - radius
The formula of a circumference of a circle:
We have the area of a circle
Substitute to the formula and solve for r:
<em>divide both sides by π</em>
Put the value of r to the formula of a circumference:
Part A: Well product of two rationals is always rational. And the sum of a rational and an irrational is irrational.
They give you too much freedom in your choice though. Like for part A, what if we let b=-1 (rational) c=pi (irrational d=pi (irrational) Then bc+d = -pi + pi = 0 (rational) Maybe they didn't want you to consider 0 because otherwise all of these options can be rational.
Do you understand the difference between a rational and irrational number? Rationals can be written as a fraction containing whole numbers. Irrationals can not. Here are some examples of rational numbers: <span>3/2</span> is rational because its a whole number divided by a whole number. 7 is a rational number because it can be written as <span>7/1</span>. <span>−4</span> is a rational number, it also can be written in this form <span><span>−4/</span>1</span>. This next one maybe seem surprising, but, 0 is a rational number. It also can be written as <span>0/1</span>, but not as <span>0/0</span> (Which is not a number).
So in the end
A: <span> virtually any sum or product involving an irrational number will be irrational.
</span>B. <span>(√7)^2 = 7 ... rational
</span>C. <span>all numbers involved are rational, so this result is rational</span>
Step-by-step explanation:
Cell Phones Are Full of Bacteria
Answer:
No
Step-by-step explanation:
Because 10 - 6.79 = 3.21