The sum of (-9) and a number (n) is multiplied by 1/2. the result is 20. what is the number?

Step-by-step explanation:

1/2 (-9+n) = 20

n=40+9

n=49

49

Step-by-step explanation:

Sum means add

-9+n

Multiply this by 1/2

1/2 (-9+n)

This is equal to 20

1/2 (-9+n) = 20

Solve

Multiply each side by 2 to get rid of the fraction

2*1/2 (-9+n) = 20*2

-9+n = 40

Add 9 to each side

-9+9 + n = 40+9

n = 49