find two consecutive integers such that the larger minus twice the smaller is -13

Question

 find two consecutive integers such that the larger minus twice the smaller is -13

Answer 1

Hi Shery,

 

Consecutive means that the second number is one more than the first number.

 

So if the first number = X, then the second number = X + 1

 

Now let's translate the English question into math . . . the large number minus twice the smaller number is -13.

 

So (X+1) - 2X = -13

 

X + 1 - 2X = -13

 

-X + 1 = -13

 

-X = -14

 

X = 14 and the second number must be 15

 

Now plug these numbers into the question to confirm that they are correct.

 

Have fun.

 

Dan

 

Answer 2

Sat a = the larger number and b = the smaller number. Since they are consecutive, a - b = 1 or a = b + 1. We also know that the larger number minus twice the smaller is -13 so a - 2b = -13. Insert the relation from the first equation into the second and solve: b + 1 - 2b = -13 -b = -14 b = 14 and since a = b + 1, a = 15