Um for the life of me can’t figure this out help

Sanjay solved the equation below. which property did he use to determine that 7x+42=42 is equivalent to 7(x+6)=42 7x+42=42 7x=0 x=0

State if it is acute obtuse or right

Yis the midpoint of xz. for each pair of points given, find the coordinates of the third point. 3. x( 5, 5), z(-1,5) 4. z( 2, 8), y(-2, 2) 7 points each xc find the indicated values. 5. b is between a and c. ab = 2x + 1, bc = 3x – 4, and ac = 62. find the value of 'x', and determine if b is a bisector. 7 points each x = bisector: yes or no? 6. m is between l and n. lm = 7x-1, mn = 2x + 4, and ln = 12. find the value of 'x' an determine if m is a bisector. x = bisector: yes or no?