-7r2 + 7r + 2 = 2
Find Discriminant

r = 1 , 0

Step-by-step explanation:

-7 + 7r + 2 = 2

-7r(r-1)=2-2

-7r(r-1)=0

r-1=0

r=1

first, you divide the triangle in two, tô form a retangle triangle. after, using pythagoream theorem:

18^2 = 14^2 + (x/2)^2

(x^2/4) + 196 = 324

x^2/4 = 324 - 196

x^2/4 = 128

x^2 = 512

x = √512

x = √2^9

x = 16√2 cm

i hope i you.