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A right triangle has a hypotenuse of 10cm. If one angle is 40°, find the length of each leg. Round to the nearest whole number. Enter the smallest leg first. Do not enter units of measurement, only numbers.

User Chops
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Answer: 6 and 8

Step-by-step explanation: A right triangle is a triangle with one angle that measures 90 degrees. The side opposite the right angle is called the hypotenuse, and the other two sides are called the legs. In this case, the hypotenuse is 10cm long.

If one angle of the triangle is 40 degrees, then the other angle must be 90-40 = 50 degrees. The remaining two angles of a triangle must add up to 180 degrees, so the third angle is 180-40-50 = 90 degrees. This means that the triangle is a right triangle, and we can use the Pythagorean theorem to find the lengths of the legs.

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the legs. In this case, we have a2 + b2 = c2, where a and b are the lengths of the legs and c is the length of the hypotenuse.

Substituting the values from the problem, we have a2 + b2 = 102, which simplifies to a2 + b2 = 100. Since we don't know the values of a and b, we can't solve for them directly. However, we can use the fact that the angle opposite the longer leg is 50 degrees, and the angle opposite the shorter leg is 40 degrees. This means that the longer leg is the opposite side of the 50-degree angle, and the shorter leg is the opposite side of the 40-degree angle.

Since the longer leg is opposite the 50-degree angle, and the shorter leg is opposite the 40-degree angle, we can use the tangent function to find the ratio of the lengths of the legs. The tangent of an angle is defined as the ratio of the opposite side to the adjacent side, so we have tangent(50 degrees) = opposite side / adjacent side = a / b, and tangent(40 degrees) = opposite side / adjacent side = b / a.

Solving for a and b, we have a = b * tangent(50 degrees) and b = a * tangent(40 degrees). Since the legs are the opposite sides of the 40- and 50-degree angles, we can substitute the values from the problem to get a = b * tangent(50 degrees) = 100 * tangent(50 degrees) and b = a * tangent(40 degrees) = 100 * tangent(40 degrees).

To find the values of tangent(50 degrees) and tangent(40 degrees), we can use a calculator or look up the values in a table of trigonometric functions. We find that tangent(50 degrees) = 1.191753592594, and tangent(40 degrees) = 0.839099631177. Substituting these values into the equations for a and b, we have a = 100 * 1.191753592594 = 119.1753592594 and b = 100 * 0.839099631177 = 83.9099631177.

Rounding to the nearest whole number, we have a = 119 and b = 84. The lengths of the legs of the triangle are therefore 6 and 8.

User Lassana
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