Can someone help me please

One friend solves
7(x + 4) = 49 by dividing each side
by 7 and then subtracting 4 from
each side. Another friend solves it by
first distributing the 7 on the left side
of the equation, then subtracting 28
from each side, and finally dividing
each side by 7. Which friend uses the
correct method? Explain.

both methods are correct

Step-by-step explanation:

Given

7(x + 4) = 49 ( divide both sides by 7 )

x + 4 = 7 ( subtract 4 from both sides )

x = 3

Given

7(x + 4) = 49 ← distribute parenthesis by 7

7x + 28 = 49 ( subtract 28 from both sides )

7x = 21 ( divide both sides by 7 )

x = 3

As shown both methods are equally valid

20

step-by-step explanation:

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2