The sum of two numbers is 25. Twice the first number minus the second is 6. Find the numbers.

Step-by-step explanation:

x + y = 25

2x - y = 6           Solve for y in this the second equation. Add y to both sides

2x  = 6 + y         The ys on the left cancel. Subtract 6 from both sides.

2x - 6 = y

Put this value of y into the first equation

x + y = 25

x + 2x - 6 = 25      Combine on the left

3x - 6 = 25           Add 6 to both sides.

3x = 25 + 6           Combine the right

3x = 31                   Divide by 3

x = 31 / 3            

x = 10.333333

x + y = 25

10.33333 + y = 25  Subtract 10.33333

y = 25 - 10.333333

y = 14.666666

x + y = 25

10.33333 + 14.66666

25 approximately.

2x - y = 6

2*10.33333 - 14.66666

20.66666 - 14.66666

6

You should note that those numbers are repeating decimals

2x - 6 = y

use the power rule  

( a b ) n = a n b n

to distribute the exponent.

apply the product rule to  

3 x 2 y 3 . ( 3 x 2 ) 2 ( y 3 ) 2

apply the product rule to  

3 x 2 . 3 2 ( x 2 ) 2 ( y 3 ) 2

raise  

3

to the power of  

2 . 9 ( x 2 ) 2 ( y 3 ) 2 multiply the exponents in   ( x 2 ) 2

.

apply the power rule and multiply exponents,  

( a m ) n = a m n . 9 x 2 ⋅ 2 ( y 3 ) 2

multiply  

2   by   2 . 9 x 4 ( y 3 ) 2

multiply the exponents in  

( y 3 ) 2 .

apply the power rule and multiply exponents,  

( a m ) n = a m n . 9 x 4 y 3

⋅

2

multiply  

3   by   2 . 9 x 4 y 6

step-by-step explanation: