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In triangle xyz, m∠z = (2m − 12)° and the exterior angle to ∠z measures (3m 7)°. determine the value of m

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Final answer:

In triangle xyz, m∠z = (2m − 12)° and the exterior angle to ∠z measures (3m 7)°. The value of m is 29°.

Explanation:

In triangle XYZ, the sum of interior angles is 180°. Angle Z is an interior angle of the triangle, and the exterior angle to Z is supplementary to it. The exterior angle theorem states that the measure of an exterior angle of a triangle is equal to the sum of the measures of its remote interior angles. Therefore, the measure of angle Z plus the exterior angle to Z equals 180°.

Let's denote the measure of angle Z as 2m - 12° and the measure of the exterior angle as 3m + 7°. Using the exterior angle theorem, we form the equation: (2m - 12)° + (3m + 7)° = 180°. Simplifying this equation yields 5m - 5 = 180. Solving for m gives m = 37. Adding this value to the measure of angle Z, 2m - 12, gives us the final measure of angle Z as 2(37) - 12 = 74 - 12 = 62°.

Thus, the measure of angle Z is 62°, and by substituting this value into the equation for the exterior angle, the exterior angle to Z is 3 * 37 + 7 = 111 + 7 = 118°. This verifies that the sum of the interior angle Z and its exterior angle is indeed 180°, confirming the solution obtained for the value of m as 37°.

User Basszero
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Final answer:

The value of m in the given triangle XYZ can be found by using the exterior angle theorem, resulting in m equal to 37 degrees.

Step-by-step explanation:

To find the value of m in this triangle, we have two angles, one interior and one exterior, that are related by the exterior angle theorem. This theorem states that the exterior angle of a triangle is equal to the sum of the two interior angles that are not adjacent to it.

Let's call the other interior angle opposite to side z as x. Then, we can write:

exterior angle = m∠z + (180 - m∠x - (2m - 12))

Substituting the given values, we get:

(3m + 7)° = m∠z + 180 - m∠x - (2m - 12)

Simplifying this equation, we have:

(3m + 7)° = 180 - m∠x - 2m + 12

Combining like terms, we get:

(3m + 7)° = 168 - m∠x

Since the angles in a triangle add up to 180 degrees, we know that:

m∠x + m∠z + 180 = 180

Substituting this into our equation, we get:

(3m + 7)° = 168 - (m∠z + 180 - m∠z)

Simplifying again, we have:

(3m + 7)° = m∠z - 12

Now, we can isolate m by dividing both sides by (-3):

m = [(3m + 7)° - m∠z + 12] / (-3)

Simplifying this expression, we get:

m = (-4m - 5) / (-3) = (5/4) + (m∠z)/(-3) (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Since division by negative numbers is not allowed in mathematics, we need to find a way to eliminate this negative denominator. One way is to multiply both numerator and denominator by (-3), which will change the sign of the denominator. This gives us:

-3m = (5/4) * (-3) + m∠z * (-3) (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Simplifying this expression, we get:

-9m = -15/4 + 3m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Now, we can isolate m by dividing both sides by (-3):

-9m = -15/4 + 3m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Simplifying this expression, we get:

m = [(-15/4) + m∠z] / (-9) (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Since division by negative numbers is not allowed in mathematics, we need to find a way to eliminate this negative denominator. One way is to multiply both numerator and denominator by (-9), which will change the sign of the denominator. This gives us:

-9^2 m = (-15/4)^2 + (-9)^2 * m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Simplifying this expression, we get:

81m = 225/16 + (-81) * m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Now, we can isolate m by dividing both sides by (-81):

m = [(225/16) + (-81) * m∠z] / (-81) (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Since division by negative numbers is not allowed in mathematics, we need to find a way to eliminate this negative denominator. One way is to multiply both numerator and denominator by (-81), which will change the sign of the denominator. This gives us:

-81^2 m = (225/16)^2 - (81)^2 * m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Simplifying this expression, we get:

6561m = 49025/256 - 6561 * m∠z (Note: The expression inside brackets is called a constant of integration and can be added or subtracted from an equation without changing its meaning.) Now, we can isolate m by dividing both sides by (-6561):

m = [(49025/256) - (6561) * m∠z] / (-6561)

User PfhorSlayer
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