Answer:
The total cost of the tablet is $840
Step-by-step explanation:
Here, we want to calculate the total cost
Let the total cost be $x
From the ratio, the total ratio is 3 + 4 + 1 = 8
so,;
3/8 * x = 315
3x = 8 * 315
x = 8/3 * 315
x = 8 * 103
x = 840
An equilateral triangle isn't a right triangle, so the Pythagorean Theorem doesn't apply directly.
But if we divide an equilateral triangle with side <em>s</em> in half along an altitude, we get two congruent right triangles each with hypotenuse <em>s </em>and one leg <em>s/2.</em>
The other leg is the altitude <em>h</em> we divided along. By the Pythagorean Theorem
The area <em>A</em> of our original equilateral triangle is now
So the area of our equilateral triangle of side 5 is
Answer: 10.8
I don't like ruining a nice exact answer with an approximation, but the question asks for one.
We could have done the above steps with 5 in particular instead of <em>s </em>but I prefer to do the general solution and substitute at the end.
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Since you read this far, I will give you the secret formula for the area S of a triangle given <em>squared</em> sides A, B, C. Your teachers won't even know this one.
Let's try it out for an equilateral triangle: