Answer:
5 (grandson's age now)
35 (son's age now)
60 (father's age now)
Step-by-step explanation:
A
Angle ABC =70
Divide 140 by 2 and apply the rule of alternante interior angles
tan(θ) = 0, 0.577, -0.577
3tan³(θ) - tan(θ) = 0
tan(θ)(3tan²(θ) - 1) = 0
tan(θ) = 0
tan²(θ) = ⅓ tan(θ) = +/- sqrt(⅓)
tan(θ) = 0, sqrt(⅓), -sqrt(⅓)
To find θ values, domain is required
