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The height of a triangle is 12 cm longer than its base. If its area is 270 square cm, what is the length of the base and the height?

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Answer:

Let's call the length of the base "b".

Since the height is 12 cm longer than the base, we can write that the height is equal to "b + 12".

We know the area of the triangle, so we can use the formula for the area of a triangle:

Area = (1/2)bh

Substituting the expressions we have for the base and the height:

270 = (1/2)(b)(b + 12)

Expanding the right side of the equation:

270 = (1/2)b^2 + (1/2)(12b)

Multiplying both sides of the equation by 2:

540 = b^2 + 12b

Combining the terms on the right side of the equation:

540 = b^2 + 12b

Subtracting 12b from both sides of the equation:

540 - 12b = b^2

Isolating b^2 on one side of the equation:

b^2 = 540 - 12b

Moving all the terms to the left side of the equation:

b^2 - 12b + 540 = 0

We can now use the quadratic formula to solve for b:

b = (-(-12) ± √((-12)^2 - 4(1)(540))) / 2(1)

Simplifying:

b = (12 ± √(144 + 2160)) / 2

b = (12 ± √(2304)) / 2

b = (12 ± 48) / 2

The two possible values of b are:

b = (12 + 48) / 2 = 30

b = (12 - 48) / 2 = -18

Since the length of the base cannot be negative, the only possible value for b is 30.

The height of the triangle can be found by using the expression "b + 12":

h = b + 12 = 30 + 12 = 42

So the base of the triangle is 30 cm and the height is 42 cm.

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