**Answer:**

**A. **

**x + 2 + 12**

**Step-by-step explanation:**

Thomas (t) = Andrew (x) * 2 + 12

**Answer:(x-3)=-(y-5)=z**

**Step-by-step explanation:**

Given

the point through which line passes is (3,5,0)

so we need a vector along the line to get the equation of line

It is given that line is perpendicular to both i+j & j+k

therefore their cross product will give us the vector perpendicular to both

v=(i+j)\times (j+k)=i-j+k

therefore we get direction vector of line so we can write

=t

i.e.

x=t+3,y=-t+5,z=t

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.

Is this math ?

Cus I am new and don’t know what to do