Answer: Choice D. P = i/rt
This is the same as saying P = i/(rt). The parenthesis are preferred in my opinion to indicate we have rt in the denominator and not just r.
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Explanation:
In the original equation, prt is the same as p*r*t. So we multiply p, r and t to get prt.
This can be thought of as p*(rt). To isolate p, we undo the multiplication done to the variable p. We will divide both sides by rt to get
i = prt
i = p*(rt)
i/(rt) = p*(rt)/(rt) ... dividing both sides by rt
i/(rt) = p
p = i/(rt)
Let Ted be x.
Ed is 7 years older = x + 7
Ed = (3/4)Ted
(x + 7) = (3/4)x
x + 7 = 3x/4
x - 3x/4 = -7
x/4 = -7
x = -28, Ted = -28 years.
(x + 7) = -28 + 7 = -21, Ed = -21 years
Goodness. We had negative numbers for the ages, well does that make sense? No it doesn't.
Our answer is correct. But the sense in the question is lacking. The question has been wrongly set.
<span>We might assume negative ages to mean before they came into the world, before birth! </span>
In a right rectangle, we have:
For your exercice, hypotenuse=12
The exercise also inform the angle 60°, then: