Numbers equation .

Question

The difference of two numbers is 7
. Three times the smaller is 9 more than the larger. Find the two numbers.

Answer 1

Here's what we know:

a - b = 7 (the difference b/n the two is 7)

a + 9 = 3b (3 times the smaller is 9 more than the larger)

 

Let's solve this using substitution. Looking at the first equation, add b to both sides:

a = b + 7

Now that we have a value, let's plug it into the second

b + 7 + 9 = 3b

b + 16 = 3b

Subtract b from both sides:

16 = 2b

Divide by 2:

8 = b

 

You can solve for a and check the work from here on out.

Answer 2

MANY, MANY problems like this one have been done and solutions are available here on WyzAnt's Resources/Answers.

Spend time there reviewing the wonderfully explained solutions (which use Algebra).