Question

When 3 is to thrice a certain number and the sum is doubled. The result is 13 more than han 5 times the original number.find the original number

Answer 1

Step-by-step explanation:

The trick is untangling all of the information, but when we do, we get the following:

2(3 + 3x) = 13 + 5x

Now it's just a matter of isolating x:

6 + 6x = 13 + 5x

6 + x = 13

x = 7

Let's check our answer:

2(3 + 3*7) = 13 + 5 * 7

2(3 + 21) = 13 + 35

2 * 24 = 48

48 = 48

Answer 2

3 is added to thrice a certain number. Let the certain number be x. So,

3+3x

The sum is doubled

(3+3x)2

The result is 13 more than 5 times the original number.

(3+3x)2=13+5x

6+6x=13+5x

x=13–6

x=7

Answer is 7