Question

Seven times a number is equal to 9 more than 4 times the number. find the number

Answer 1

Represent 'a number' by x
7 times x equals 9 more than 4 times x
7 times x=9+4 times x
7x=9+4x
subtract 4x from both sides
3x=9
divide 3
x=3

the number is 3