Question

What does twice the product of 3 and a number exceeds the sum of the number and 80 by 10. what is that number?

Answer 1

let x be the number
twice the product of 3 and a number means
2(3x)

the sum of the number and 80 by 10 means
x+80+10
putting this altogether creates an equation

2(3x)=x+80+10
6x=x+90 (expanded the brackets on the left hand side and added 80 +10 on the left)
5x=90 (subtracted x to both sides)
x=90/5
x=18

Therefore the number is 18.

Answer 2

so 2(3x)=x+80+10
distribute
6x=x+90
subtract x from both sides
5x=90
divide both sides by 5
x=18