⦁explain the difference between  ""4  times the sum of  x  and  y""  and ""the sum of  4  times  x  and  y.""

In the first case, you perform the sum and then multiply by 4:

The sum of x and y ---> x+y

Four times the sum of x and y --->4(x+y)

In the second case, only x is multiplied by 4:

4 times x > 4x

The sum of 4 times x and y ---> 4x+y

1) the property is   ixi = a ⇔x = a   o x = -a

4(x-5)+3= 15⇒4x-20+3 = 15⇒4x-17= 15⇒4x = 15+17⇒4x = 32⇒x =32/4= 8

4(x-5) +3= -15⇒4x-20 +3 = -15⇒4x-17= -15⇒4x =-15+17⇒4x = 2⇒x =2/4= 1/2

the values are x =8 and x = 0,5