The vertices of are D(7, 3), E(4, -3), and F(10, -3). Write a paragraph proof to prove that is isosceles.

See explanation

Step-by-step explanation:

Distance Formula:

Isosceles Triangle: 2 sides are the same

Since we have 2 distances between the vertices the same, we have an isosceles triangle.

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1

look a the sides they are perpendicular