In this figure, m∠3 = (2x + 15)° and m∠6 = (3x + 10)°. what value of x makes a∥b? enter your answer in the box.in  △abc,  m∠a  =  (4x  +  5)°  and  m∠b  =  (5x−1)°  what  is  m∠c? a.6°b.29°c.180°d.122°

For First Question:
As, we find the value  of x for parallel condition of line a and b
so, m∠3 = m∠1 and m∠2 = 180°-m∠1 = 180°-(2x+15)° [ As straight line contain total 180°]
Now,
m∠2 = m∠6 [ Because they are corresponding angles]
180-(2x+15)=(3x+10)
180=3x+10+2x+15
x= 31 satisfies the condition of a||b

For second Question:
As, it is issoceles triangle So side AC = side BC So, m∠A=m∠B
4x+5=5x-1
x=6
So,
m∠A=29° and triangle contain total 180° 
m∠C=180-29-29
       =122°
Option D is correct