it might be 5 if you subtract 13 from 8
let point A has coordinates (-9;12),B(-3;12),C(-5;10) and D(-11;10).Then the vector AB={6;0}, BC={2;-2}, CD={6;0}, AD={2;-2} and their and the length of the vectors
![|AB| = |CD| = \sqrt{ {6}^{2} + {0}^{2} } = \sqrt{36} = 6 \\ |BC| = |AD| = \sqrt{ {2}^{2} + {( - 2)}^{2} } = \sqrt{8}](https://tex.z-dn.net/?f=%20%7CAB%7C%20%3D%20%7CCD%7C%20%3D%20%5Csqrt%7B%20%7B6%7D%5E%7B2%7D%20%2B%20%7B0%7D%5E%7B2%7D%20%7D%20%3D%20%5Csqrt%7B36%7D%20%3D%206%20%5C%5C%20%7CBC%7C%20%3D%20%7CAD%7C%20%3D%20%5Csqrt%7B%20%7B2%7D%5E%7B2%7D%20%2B%20%7B%28%20-%202%29%7D%5E%7B2%7D%20%7D%20%3D%20%5Csqrt%7B8%7D%20)
![p = 6 + 6 + \sqrt{8} + \sqrt{8} = \\ = 12 + 2 \sqrt{8} = 17.66\approx18](https://tex.z-dn.net/?f=p%20%3D%206%20%2B%206%20%2B%20%5Csqrt%7B8%7D%20%2B%20%5Csqrt%7B8%7D%20%3D%20%5C%5C%20%3D%2012%20%2B%202%20%5Csqrt%7B8%7D%20%3D%2017.66%5Capprox18)
Answer:
3/25
f(x) = abx
f(0) = ab0 = a(1) = a = 3 (given)
f(1) = 3b1 = 3b = 15 ⇒ b = 5
f(-1) = 3•5-1 = 3/25
2x-2-3x3 =-13. -13 is the answer
Triangle ABC has angles 130, 15 and 35
Triangle DEF has angles 35, 15, and 130
4) The triangles have 3 pairs of congruent angles.