Question

Measure of the other acute angle?

Answer 1

Step-by-step explanation:

step 1. the 3 internal angles of a triangle add up to 180°. let x be the 3rd angle

step 2. x + 34 + 72 = 180

step 3. x = 74°.

step 4. for problem 5 let the internal angles be a, b, and c

step 5. so b = 2a - 10, c = b + 25

step 6. we also know that a + b + c = 180

step 7. so a + (2a - 10) + (b + 25) = 180 by substitution

step 8. a + (2a - 10) + ((2a - 10) + 25) = 180 also by substitution

step 9. 3a - 10 + 2a + 15 = 180

step 10. 5a + 5 = 180

step 11. a = 35°

step 12. therefore b = 2a - 10 = 60°, c = 85°.