2. Write a proof for the biconditional using the conditional and converse.

A triangle is equilateral if and only if all the side lengths of the
triangle are equal.

3. Write a proof for the biconditional using the inverse and
contrapositive.
x24 if and only if 3x 12.

Write a proof for this statement. If a quadrilateral is a square, then the quadrilateral is a rectangle.

so, converting firstly the mixed fractions to improper fractions and then "adding".

isaiah walks 3 miles due north, turns and then 5 miles due east. how far is he from his starting point?

a^2 + b^2 = c^2

let c = distance from starting point.

(3)^2 + (5)^2 = c^2

9 + 25 = c^2

34 = c^2

sqrt{34} = sqrt{c^2}

sqrt{34} = c

step-by-step explanation:

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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