Question #7d717

Feb 9, 2018

$x = 9 , y = 7$ or
$\left(9 , 7\right)$

Explanation:

Write a system that matches up with the information:

$x + y = 16$
$x - y = 2$

You can solve this with elimination. In this case, add them together to get rid of y.

$2 x = 18$

$x = 9$

Plug in to solve for y.

$9 + y = 16$

$y = 7$

Feb 9, 2018

$9 \mathmr{and} 7$

Explanation:

.

Let the numbers be $x$ and $y$.

$x + y = 16$

$x - y = 2$

If we add the two equations we get:

$2 x = 18$

$x = 9$

Now, we can plug this into any of the equations to solve for $y$:

$x + y = 16$

$9 + y = 16$

$y = 16 - 9$

$y = 7$

Feb 9, 2018

9 and 7

Explanation:

Well, what you have is, 2 equations in 2 unknowns. Which is enough to find a solution. There are a couple of ways to proceed, which no doubt you'll learn. For this example, probably the simplest is substitution.

$a + b = 16$
$a - b = 2$

From the second equation, we can say that:

$a = 2 + b$

...and now we substitute this value of a in the first equation:

$\left(2 + b\right) + b = 16$
$2 b + 2 = 16$
$2 b = 14$
$b = 7$
...and now we can plug this back into the second equation, and solve for a:
$a - 7 = 2$
$a = 9$

GOOD LUCK