The options are wrong lol, it is -1/8
Answer:
Step-by-step explanation:
6x^2+5x+1=0
Descr= b^2-4ac
Descr= 25-24=1
X1= (-b+√descr)/2a = (-5+1)/12= -1/3
X2= (-b-√descr)/2a = (-5-1)/12= -1/2
the 3rd vertex is on the x axis line which means Y =0
since the longer leg is twice as long as the shorter leg and the length of the shorter leg is a, then twice the length would be 2a ( 2 times a)
so the 3rd vertex is (2a,0)
M is a midpoint of BC so:

Length of MA:

Length of NB:
F(g(x)) where you see an 'x' in f(x) put a g:
f(g(x)) = 1/(g-7), now step by step: g - 7 = 6/x+7-7=6/x, and 1/(g-7)=1/(6/x)=x/6!
I let the second one for you. Sorry if you disagree!