What is the value of f

f = 22

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.

140° is an exterior angle of the triangle, thus

4f + 1 + 51 = 140, that is

4f + 52 = 140 ( subtract 52 from both sides )

4f = 88 ( divide both sides by 4 )

f = 22

Area = 42 sqaure inches

Length =7

Area = l x width

if the width is X then 7x=42 and x= 42/7 = 6

there X (width) is 6

perimeter thus is 7+7+6+6= 26

The answer is 26