Answer:
F
Step-by-step explanation:
Answer is to the question is 20
9x-20=7
9x=27
x=3
Hope that helps you :)
Answer:

Step-by-step explanation:
We need to find m ∠EGD.
From the given figure, we can see that, ∠BGA & ∠EGD are vertically opposite angles (opposite angles that share the same vertex ⟶ G).
Also, vertically opposite angles are equal to each other.
Given, ∠BGA = 30°
So, ∠EGD = ∠BGA = 30°.

When a quadratic equation ax^2+bx+c has a double root, the discriminant,
D=b^2-4ac=0
Here
a=2,
b=b,
c=18
and
D=b^2-4ac=b^2-4*2*18=0
solve for b
b^2-144=0
=> b= ± sqrt(144)= ± 12
So in order that the given equation has double roots, the possible values of b are ± 12.