Answer:
m<ABC = 41°
m<DBC = 35°
m<NDF = 77°
Step-by-step explanation:
Problem 1:
Given, m<ABD = 76°, m<ABC = (7x - 1), m<DBC = (5x + 5)
m<ABC + DBC = m<ABD (angle addition postulate)
[tex] (7x - 1) + (5x + 5) = 76 [/tex] (substitution)
Solve for x
[tex] 7x - 1 + 5x + 5 = 76 [/tex]
Collect like terms
[tex] 7x + 5x - 1 + 5 = 76 [/tex]
[tex] 12x + 4 = 76 [/tex]
Subtract 4 from each side
[tex] 12x + 4 - 4 = 76 - 4 [/tex]
[tex] 12x = 72 [/tex]
Divide each side by 12
[tex] x = 6 [/tex]
Find m<ABC
m<ABC = (7x - 1)
Plug in the value of x
m<ABC = 7(6) - 1 = 42 - 1 = 41°
Find m<DBC
m<DBC = (5x + 5)
Plug in the value of x
m<DBC = 5(6) + 5 = 30 + 5 = 35°
Problem 2:
<JKH and <NDF are corresponding angles. Corresponding angles are congruent.
Given that m<JKH = 77°, m<NDF = 77° (corresponding angles are equal).
