Use the relationships between angle pairs to find the measure of angle f.

Angle a and angle b are complementary angles. Write an equation to represent the relationship between angle a and angle b.
dºcºbºaºfºeº
Great job!
Angle a and angle f are supplementary angles. Write an equation to represent the relationship between angle a and angle f.
a+b=90
dºcºbºaºfºeº

1 answer

To find the measure of angle \( f \), we can start with the relationships you provided.

  1. Angle \( a \) and angle \( b \) are complementary angles, which gives us the equation: \[ a + b = 90^\circ \]

  2. Angle \( a \) and angle \( f \) are supplementary angles, leading to the equation: \[ a + f = 180^\circ \]

Steps to Find Angle \( f \):

  1. Start with the equation for supplementary angles: \[ f = 180^\circ - a \]

  2. From the first equation \( a + b = 90^\circ \), you can express \( b \) in terms of \( a \): \[ b = 90^\circ - a \]

  3. Substitute this expression for \( a \) into the supplementary angle equation: \[ f = 180^\circ - a \]

  4. Notice that we need further information about angle \( a \) or \( b \) to isolate the value of \( f \). However, we can express all angles in terms of one of them.

You can use either \( a \) or \( b \) to find \( f \). For example, if you have a specific value for \( a \) or \( b \), substitute it back into the equations to find \( f \).

Example:

If you know \( a = 30^\circ \):

  • Substitute into \( a + b = 90^\circ \): \[ 30^\circ + b = 90^\circ \rightarrow b = 60^\circ \]

  • Now substitute \( a \) into \( f = 180^\circ - a \): \[ f = 180^\circ - 30^\circ = 150^\circ \]

Thus, if \( a = 30^\circ \), then \( f = 150^\circ \). You would need a similar approach if you have another known angle.