Answer:9
Step-by-step explanation: x+4=13
x=13-4
x=9
Answer:
= One-half more than three-fourths of a number
= Three-fourths minus one-half of a number
= three-fourths minus the sum of a number and one-half
Step-by-step explanation:
Suppose x be an unknown number.
∵ 3/4th of a number = 
= One-half more than three-fourths of a number
Now, half of a number = 
= Three-fourths minus one-half of a number
Sum of a number and one-half = 
= three-fourths minus the sum of a number and one-half
He messed up step 2 he added instead of multiplying
That is true because factors of 40 are 10,5