contestada

the sum of twice a number and a second number is 61. the second number is 17 less than four times the first. what are the two numbers?

Respuesta :

We have two numbers, let's say a and b.

We must build our equations.


Sum = addition, and twice = multiplication, so:

[tex]2a + b = 61[/tex]

where a represents "twice a number"


Less = subtraction, and four times = multiplication, so:

[tex]b = 4a - 17[/tex]


Now we have our two equations:

[tex]2a + b = 61\\b = 4a - 17[/tex]


One of these is already solved for a variable, so we can substitute it.

Substitute b into the first equation:

[tex]2a + 4a - 17 = 61\\6a - 17 = 61\\6a = 78\\a = 13[/tex]

We have solved for a's int value, being 13.


Plug a into the second equation and solve for b:

[tex]b = 4(13) - 17\\b = 52 - 17\\b = 35[/tex]

We have solved for b's integer value, 35.


Now that we have both numbers, let us check our solution:

a = 13

b = 35


The sum of twice a number and a second number is 61:

13(2) + 35 = 26 + 35 = 61 ✓

The second number is 17 less than four times the first:

35 = 4(13) - 17 = 52 - 17 = 35 ✓


Our answers are:

a = 13

b = 35