Answer to this question ?

(x - 10)(x - 3)

Step-by-step explanation:

You have to think of numbers that multiply up to 30 and add up to 13. So you eliminate the numbers down to 10 and 3, because you can add up to 13 and multiply to 30. Now you have to find how it adds up to negative 13 and multiply it to postive 30. 2 negatives make a positive when multiplying, and 2 negatives added together make another negative, so your roots are 10 and 3. Put that into factored form and you have (x - 10)(x - 3).

Alternatively you can either graph to find its zeros or guess-and-check.

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9