I'm struggling with this lesson on Study Island, please help! Which algebraic expression is equivalent to the expression below?

(4x + 13) + 11
A.
4x + (13 - 11)
B.
(4 + 13)(x + 11)
C.
4x + (13 + 11)
D.
17x + 11

C

Step-by-step explanation:

Associative property states that when three or more numbers are added, the sum is the same regardless of the grouping.

This means that (4x + 13) + 11 is the same as C. 4x + (13 + 11)

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116