The sum of two numbers is 21. the second number is six times the first number. work out the two numbers.

Pretend that x and y represents the 2 numbers that we need to find.

According to the information, we know that:

x + y = 21

6x = y

Replace y in the first equation with 6x (because they are equal to each other according to the second equation):

x + y = 21

x + 6x = 21

7x = 21

x = 21/7 = 3

Now have two ways to find y, both will give us the same result:

3 + y = 21 ⇔ y = 21 - 3 = 18

6 · 3 = y ⇔ y = 18

So the numbers that we need to find are 3 and 18.

step-by-step explanation:

to find if any function is an inverse of the other, put the first equation in as x in the next one. then simplify and solve. if at the end you get the statement y = x, then it is an inverse. if you get anything else, it is not.

answer: 80,000

step-by-step explanation:

the population doubles every day.

10,000*2=20,000 day 4

20,000*2=40,000 day 5

40,000*2=80,000 day 6