Jillian is 5 years old. She has an older brother whose age is represented by the expression 2x+3, where x represents Jillian's age. How old is her brother?

13

Step-by-step explanation:

2(5) = 10, +3 = 13 years old,, just use order of operations and plug in jillians age for the x

7

Step-by-step explanation:

2x2 = 4+3=7 so her brother is 7

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