What are the answers to all of these questions?

We have that

N 11)
a) graph the equation  y=x²-3x-10

using a graph tool
see the attached figure

b) Determine the roots of the equations
the roots of the equations are the values for y=0
x²-3x-10=0
x²-3x-10=(x+2)*(x-5)=0
the roots are
x1=-2
x2=5

see the attached figure problem 11

N 12) what is the value of x in the equation? 
3x²=7x

3x²=7x-------> 3x²-7x=0--------> x*(3x-7)=0

x1=0
3x-7=0------> 3x=7------> x=7/3

the values of x are
x1=0
x2=7/3---> 2.33
see the attached  figure problem 12

N 13) what is the value of x in the equation? 
x²-5x=6----------> x²-5x-6=0
x²-5x-6=0-------> (x+1)*(x-6)=0
the values of x are
x1=-1
x2=6

N 14) what is the value of x in the equation? 
2x²-5x=12--------> 2x²-5x-12=0

using a graph tool
see the attached figure problem N 14
2x²-5x-12=0----------> (x+3/2)*(x-4)=0

the values of x are
x1=-3/2
x2=4