What type of triangle is formed by joining the points d(7, 3), e(8, 1), and
f(4, -1)?
a.
equilateral triangle
b.
isosceles triangle
c.
right triangle
d.
acute scalene triangle
e.
obtuse scalene triangle

D(7, 3), E(8, 1), and  F(4, -1)

We calculate the squared distances between the points:

Since we have a right triangle with hypotenuse DF.

3x + 18 = 147°

step-by-step explanation:

3x + 18 = 147°, because the value of the central angle is equal to the value of the arc formed by it.

i hope i you.