The sum of the ages of Martin and his son Sherwin is 47 years. Martin's age is 2 years more than 4 times essment 3
the
age of Sherwin. Find their present age.

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

you already gave the answer

step-by-step explanation: