The equation is y^2=16x and the directrix is x=-4
Richard is 14 years old and Teo is 6 years old.
Step-by-step explanation:
Let,
Richard's age = x
Teo's age = y
Combined age = 20 years
According to given statement;
x+y=20 Eqn 1
x = 2y+2 Eqn 2
Putting value of x from Eqn 2 in Eqn 1

Dividing both sides by 3

Putting y=6 in Eqn 2

Richard is 14 years old and Teo is 6 years old.
Keywords: linear equation, substitution method
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