#19. X=7
#20. Xwy=24°
#21.xwz=48°
Step-by-step explanation:
For 19, you put the equation equal to each other and solve for x
2x+10=4x-4
14=2x
7=x
Then for 20, I substituted x in 4x-4
4(7)-4=24
Then for 21, I did 24(2) because since the equation are equal they both are 24° so Hoped this helped